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Purpose: To investigate fundus autofluorescence (AF) characteristics in the Abca4(-/-) mouse, an animal model for AMD and Stargardt disease, and to correlate findings with functional, structural, and biochemical assessments., Methods: Blue (488 nm) and near-infrared (790 nm) fundus AF images were quantitatively and qualitatively analyzed in pigmented Abca4(-/-) mice and wild type (WT) controls in vivo. Functional, structural, and biochemical assessments included electroretinography (ERG), light and electron microscopic analysis, and A2E quantification. All assessments were performed across age groups., Results: In Abca4(-/-) mice, lipofuscin-related 488 nm AF increased early in life with a ceiling effect after 6 months. This increase was first paralleled by an accumulation of typical lipofuscin granules in the retinal pigment epithelium (RPE). Later, lipofuscin and melanin granules decreased in number, whereas melanolipofuscin granules increased. This increase in melanolipofuscin granules paralleled an increase in melanin-related 790 nm AF. Old Abca4(-/-) mice revealed a flecked fundus AF pattern at both excitation wavelengths. The amount of A2E, a major lipofuscin component, increased 10- to 12-fold in 6- to 9-month-old Abca4(-/-) mice compared with controls, while 488 nm AF intensity only increased 2-fold. Despite pronounced lipofuscin accumulation in the RPE of Abca4(-/-) mice, ERG and histology showed a slow age-related thinning of the photoreceptor layer similar to WT controls up to 12 months., Conclusions: Fundus AF can be used to monitor lipofuscin accumulation and melanin-related changes in vivo in mouse models of retinal disease. High RPE lipofuscin may not adversely affect retinal structure or function over prolonged time intervals, and melanin-related changes (melanolipofuscin formation) may occur before the decline in retinal function.

Purpose: To develop a reproducible laboratory model to simulate a battlefield foveal laser injury and to test potential neuroprotective effects of a single injection treatment that might be administered in a military setting., Methods: Frequency-doubled 532-nm Nd:YAG laser was used to induce a threshold retinal injury bilaterally in transgenic reporter mice that have fluorescent cones. Intravitreal injection of ciliary neurotrophic factor (CNTF) was then administered to the lasered eye and compared with a contralateral sham injection of saline. The effect on fluorescent cone cell survival was quantified using a confocal scanning laser ophthalmoscope (cSLO), TUNEL assays, and quantitative real-time PCR (qPCR)., Results: At 3 weeks post-laser, cSLO imaging showed that the proportion of surviving cones expressing green fluorescent protein (GFP) was greater in CNTF-treated (54.1 ± 5.15% of baseline count) than in sham-injected eyes (28.7 ± 4.4%), which was accompanied by a reduction in TUNEL-positive cells. This difference in cone survival persisted at the 6-week point (treated, 39.6 ± 3.2% versus sham, 18.0 ± 3.8%). These changes were accompanied by a reduction in TUNEL-positive cells. The Bcl-2/Bax ratio was increased in CNTF-treated eyes at 1 week postlaser exposure relative to controls., Conclusions: A single intravitreal injection of CNTF protein was shown to improve cone survival when administered immediately after laser exposure. Similar treatments with CNTF might also have a role in attenuating retinal laser damage sustained by combat personnel in the military setting.

Purpose: To evaluate different therapies for choroidal neovascularization (CNV) due to angioid streaks (AS)., Methods: Studies were identified by a systematic literature search and were included in the analysis based on predefined criteria. Primary outcome measure was change in best-corrected visual acuity (BCVA)., Results: Fifty-four relevant studies were identified and included mostly uncontrolled case series. No randomized controlled trials were available. Treatment with vascular endothelial growth factor inhibitors improved or stabilized BCVA in all case series. Photodynamic therapy slowed down disease progression with stabilization or decrease of BCVA. Individual BCVA and follow-up data for each treated eye were reported in >160 cases for both treatments, vascular endothelial growth factor inhibitors and photodynamic therapy. In a pooled analysis of those studies, the difference of mean change in BCVA between both treatment groups was estimated as approximately 6 lines (0.59 logMAR [95% confidence interval, 0.38-0.8; P < 0.0001]). A better baseline BCVA was associated with a better BCVA outcome (P < 0.0001). Laser photocoagulation yielded comparable results as photodynamic therapy but application was mostly restricted to extrafoveal lesions, was complicated by frequent recurrences, and led to more retinal damage with subsequent absolute scotomas. Combination therapies seem to be not superior to monotherapy., Conclusion: Intravitreal vascular endothelial growth factor inhibitors are currently the most effective treatment of CNV due to angioid streaks.

Macular telangiectasia type 2 is a bilateral disease of unknown cause with characteristic alterations of the macular capillary network and neurosensory atrophy. Its prevalence may be underestimated and has recently been shown to be as high as 0.1% in persons 40 years and older. Biomicroscopy may show reduced retinal transparency, crystalline deposits, mildly ectatic capillaries, blunted venules, retinal pigment plaques, foveal atrophy, and neovascular complexes. Fluorescein angiography shows telangiectatic capillaries predominantly temporal to the foveola in the early phase and a diffuse hyperfluorescence in the late phase. High-resolution optical coherence tomography (OCT) may reveal disruption of the photoreceptor inner segment-outer segment border, hyporeflective cavities at the level of the inner or outer retina, and atrophy of the retina in later stages. Macular telangiectasia type 2 shows a unique depletion of the macular pigment in the central retina and recent therapeutic trials showed that such depleted areas cannot re-accumulate lutein and zeaxanthin after oral supplementation. There have been various therapeutic approaches with limited or no efficacy. Recent clinical trials with compounds that block vascular endothelial growth factor (VEGF) have established the role of VEGF in the pathophysiology of the disease, but have not shown significant efficacy, at least for the non-neovascular disease stages. Recent progress in structure-function correlation may help to develop surrogate outcome measures for future clinical trials. In this review article, we summarize the current knowledge on macular telangiectasia type 2, including the epidemiology, the genetics, the clinical findings, the staging and the differential diagnosis of the disease. Findings using retinal imaging are discussed, including fluorescein angiography, OCT, adaptive optics imaging, confocal scanning laser ophthalmoscopy, and fundus autofluorescence, as are the findings using visual function testing including visual acuity and fundus-controlled microperimetry. We provide an overview of the therapeutic approaches for both non-neovascular and neovascular disease stages and provide a perspective of future directions including animal models and potential therapeutic approaches., (2012 Elsevier Ltd. All rights reserved)

Adeno-associated viral vectors (AAV) have been shown to be safe in the treatment of retinal degenerations in clinical trials. Thus, improving the efficiency of viral gene delivery has become increasingly important to increase the success of clinical trials. In this study, structural domains of different rAAV serotypes isolated from primate brain were combined to create novel hybrid recombinant AAV serotypes, rAAV2/rec2 and rAAV2/rec3. The efficacy of these novel serotypes were assessed in wild type mice and in two models of retinal degeneration (the Abca4(-/-) mouse which is a model for Stargardt disease and in the Pde6b(rd1/rd1) mouse) in vivo, in primate tissue ex-vivo, and in the human-derived SH-SY5Y cell line, using an identical AAV2 expression cassette. We show that these novel hybrid serotypes can transduce retinal tissue in mice and primates efficiently, although no more than AAV2/2 and rAAV2/5 serotypes. Transduction efficiency appeared lower in the Abca4(-/-) mouse compared to wild type with all vectors tested, suggesting an effect of specific retinal diseases on the efficiency of gene delivery. Shuffling of AAV capsid domains may have clinical applications for patients who develop T-cell immune responses following AAV gene therapy, as specific peptide antigen sequences could be substituted using this technique prior to vector re-treatments.

Pseudoxanthoma elasticum (PXE) is an inherited multi-system disorder characterized by ectopic mineralization and fragmentation of elastic fibers in the skin, the elastic laminae of blood vessels and Bruch's membrane in the eye. Biallelic mutations in the ATP-binding cassette (ABC) transporter gene ABCC6 on chromosome 16 are responsible for the disease. The pathophysiology is incompletely understood. However, there is consent that a metabolic alteration leads to dysfunction in extracellular calcium homeostasis and subsequent calcification of connective tissues rich in elastic fibers. This review summarizes and aims at explaining the variety of phenotypic ocular findings in patients with PXE. Specialized imaging techniques including white light fundus photography, blue light autofluorescence, near-infrared confocal reflectance imaging, high resolution optical coherence tomography, fluorescein and indocyanine green (ICG) angiography have revealed characteristic lesions at the ocular fundus of PXE patients. These include the classic signs of angioid streaks, peau d'orange, comet lesions, and choroidal neovascularizations (CNVs), but also the more recently recognized features such as chorioretinal atrophy, subretinal fluid independent from CNV, pattern dystrophy-like changes, debris accumulation under the retinal pigment epithelium, reticular drusen and a decreased fluorescence on late phase ICG angiography.

Age-related macular degeneration (AMD) is the most common cause of blindness in Germany. Due to the demographic development a further increase of affected patients is to be expected. Improved understanding of AMD pathogenesis resulted from the molecular biological approaches in recent years and showed an association of genetic factors with AMD. The complement factor H gene and the second high-risk locus ARMS2 in particular were found to contribute a significant risk for development of the disease. Ageing and environmental factors, such as smoking, modulate the individual genetic risk profile. A detailed understanding of the complex AMD pathogenesis is also relevant in ophthalmological practice to understand new treatment strategies. In this review we aim to give an overview of the interplay of ageing, external environmental factors and genetic risk variants leading to AMD.

One strategy to restore vision in retinitis pigmentosa and age-related macular degeneration is cell replacement. Typically, patients lose vision when the outer retinal photoreceptor layer is lost, and so the therapeutic goal would be to restore vision at this stage of disease. It is not currently known if a degenerate retina lacking the outer nuclear layer of photoreceptor cells would allow the survival, maturation, and reconnection of replacement photoreceptors, as prior studies used hosts with a preexisting outer nuclear layer at the time of treatment. Here, using a murine model of severe human retinitis pigmentosa at a stage when no host rod cells remain, we show that transplanted rod precursors can reform an anatomically distinct and appropriately polarized outer nuclear layer. A trilaminar organization was returned to rd1 hosts that had only two retinal layers before treatment. The newly introduced precursors were able to resume their developmental program in the degenerate host niche to become mature rods with light-sensitive outer segments, reconnecting with host neurons downstream. Visual function, assayed in the same animals before and after transplantation, was restored in animals with zero rod function at baseline. These observations suggest that a cell therapy approach may reconstitute a light-sensitive cell layer de novo and hence repair a structurally damaged visual circuit. Rather than placing discrete photoreceptors among preexisting host outer retinal cells, total photoreceptor layer reconstruction may provide a clinically relevant model to investigate cell-based strategies for retinal repair.

Background: The pathophysiology of pigment epithelial detachment (PED) secondary to age-related macular degeneration (AMD) is as yet incompletely understood and treatment remains challenging. Spectral domain optical coherence tomography (SD-OCT) allows for improved morphological characterisation of the space underneath the retinal pigment epithelium (RPE)., Objective: To investigate eyes with PED for structures underneath the detached RPE cell layer., Methods: In a retrospective observational case study, SD-OCT scans of AMD-related PEDs were assessed for the presence of distinctive morphological features in the space between the detached RPE and inner Bruch's membrane., Results: Structures present in the space between the detached RPE and Bruch's membrane were found in 14 of 90 eyes with AMD-related PED. Each of these eyes shows hyper-reflective material underneath the PED, presenting as highly reflective, multilayered, laminar structures, usually orientated parallel to Bruch's membrane., Conclusions: The findings indicate that SD-OCT may be useful for a more refined phenotypic stratification of AMD-associated PED. Further studies are warranted to explore the correlates on other imaging modalities, to investigate the composition of this material and to assess the potential prognostic relevance of this new finding.

Purpose: To investigate the feasibility and to identify sources of experimental variability of quantitative and qualitative fundus autofluorescence (AF) assessment in mice., Methods: Blue (488 nm) and near-infrared (790 nm) fundus AF imaging was performed in various mouse strains and disease models (129S2, C57Bl/6, Abca4(-/-), C3H-Pde6b(rd1/rd1), Rho(-/-), and BALB/c mice) using a commercially available scanning laser ophthalmoscope. Gray-level analysis was used to explore factors influencing fundus AF measurements., Results: A contact lens avoided cataract development and resulted in consistent fundus AF recordings. Fundus illumination and magnification were sensitive to changes of the camera position. Standardized adjustment of the recorded confocal plane and consideration of the pupil area allowed reproducible recording of fundus AF from the retinal pigment epithelium with an intersession coefficient of repeatability of ±22%. Photopigment bleaching occurred during the first 1.5 seconds of exposure to 488 nm blue light (∼10 mW/cm(2)), resulting in an increase of fundus AF. In addition, there was a slight decrease in fundus AF during prolonged blue light exposure. Fundus AF at 488 nm was low in animals with an absence of a normal visual cycle, and high in BALB/c and Abca4(-/-) mice. Degenerative alterations in Pde6b(rd1/rd1) and Rho(-/-) were reminiscent of findings in human retinal disease., Conclusions: Investigation of retinal phenotypes in mice is possible in vivo using standardized fundus AF imaging. Correlation with postmortem analysis is likely to lead to further understanding of human disease phenotypes and of retinal degenerations in general. Fundus AF imaging may be useful as an outcome measure in preclinical trials, such as for monitoring effects aimed at lowering lipofuscin accumulation in the retinal pigment epithelium.

Genetic mutations are the cause of inherited retinal dystrophies. The underlying genetic basis of these diseases suggests that a gene therapy approach is logical either to replace or reduce the expression of defective genes. The first proof-of-concept clinical studies in patients with Leber's congenital amaurosis have suggested that retinal gene therapy is safe and potentially effective, at least for specific disease entities. In contrast to pharmacological treatment gene therapy has the advantage of being able to express a protein within specific cell populations and is a potentially definitive therapy. Besides replacing deficient genes in inherited diseases, additional strategies that might broaden the application of retinal gene therapy are also being developed. These include the permanent expression of neuroprotective substances or photosensitive molecules (so-called optogenetics). This overview discusses the current clinical strategies and potential problems of retinal gene therapy.

In the developed world, diseases of the retina are common causes of untreatable blindness. In many cases, a genetic component to the aetiology has been identified, making the development of gene-based treatments a logical long-term goal. The clinical strategy for retinal gene therapy broadly encompasses two distinct advantages over systemic drug delivery. First is that gene delivery can limit expression of a therapeutic protein to a specific target cell, which is rarely possible even with local drug delivery methods. Second, by delivering DNA that remains stable and non-degraded, gene expression and hence protein production could in theory be indefinite, obviating the need for repeated tablets or injections. Viruses have evolved distinct mechanisms, such as receptor mediated uptake and genomic integration, which efficiently encompass these two properties. For non-viral gene therapy approaches, however, nuclear localization and stable long-term transgene expression remain significant hurdles that need to be overcome. The challenge of non-viral gene therapy is therefore to harness current laboratory and molecular-based techniques to develop a man-made system that can approach the efficiency of a natural biological process. In the unique environment of the retina, this goal may not be insurmountable and would overcome the major limiting factor of adeno-associated viral vectors, which is the size of gene that can be delivered., (© 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.)

Objective: To investigate the impact of pseudoxanthoma elasticum (PXE), a rare hereditary disease of concurrent vision impairment (VI) and cardiovascular complications (CVCs), on vision-related (VRQoL) and health-related quality of life (HRQoL)., Methods: VRQoL and HRQoL were assessed using the Impact of Vision Impairment (IVI) questionnaire and the Short Form Health Survey (SF-36) in 107 PXE patients. Patients were stratified into four groups: A = no VI or CVC; B = CVCs only; C = VI only; and D = both VI and CVCs., Results: Following Rasch analysis, the IVI was found to function as a vision-specific functioning and emotional well-being subscale, and the SF-36 as a health-related physical functioning and mental health subscale. The presence of VI and CVC were significant predictors of vision-specific functioning and emotional well-being (p < 0.001), with a clinically meaningful decrement in vision-specific functioning in patients with VI. No associations were found for the SF-36 Physical Functioning and Mental Health scores between any groups., Conclusions: Vision impaired patients with PXE report significantly poorer vision-specific functioning than PXE patients without VI. In contrast, the relative impact of PXE on reported general HRQoL was much less. Our results suggest that vision impairment has the larger impact on QoL in this sample.

In this study, we performed an in-depth analysis of the neurologic and ophthalmologic phenotype in a patient with Pitt-Hopkins syndrome (PTHS), a disorder characterized by severe mental and motor retardation, carrying a uniallelic TCF4 deletion, and studied a zebrafish model. The PTHS-patient was characterized by high-resolution magnetic resonance imaging (MRI) with diffusion tensor imaging to analyze the brain structurally, spectral-domain optical coherence tomography to visualize the retinal layers, and electroretinography to evaluate retinal function. A zebrafish model was generated by knockdown of tcf4-function by injection of morpholino antisense oligos into zebrafish embryos and the morphant phenotype was characterized for expression of neural differentiation genes neurog1, ascl1b, pax6a, zic1, atoh1a, atoh2b. Data from PTHS-patient and zebrafish morphants were compared. While a cerebral MRI-scan showed markedly delayed myelination and ventriculomegaly in the 1-year-old PTHS-patient, no structural cerebral anomalies including no white matter tract alterations were detected at 9 years of age. Structural ocular examinations showed highly myopic eyes and an increase in ocular length, while retinal layers were normal. Knockdown of tcf4-function in zebrafish embryos resulted in a developmental delay or defects in terminal differentiation of brain and eyes, small eyes with a relative increase in ocular length and an enlargement of the hindbrain ventricle. In summary, tcf4-knockdown in zebrafish embryos does not seem to affect early neural patterning and regionalization of the forebrain, but may be involved in later aspects of neurogenesis and differentiation. We provide evidence for a role of TCF4/E2-2 in ocular growth control in PTHS-patients and the zebrafish model.

Age-related macular degeneration is a leading form of blindness in Western countries and is associated with a common SNP (rs 1061170/Y402H) in the Factor H gene, which encodes the two complement inhibitors Factor H and FHL1. However, the functional consequences of this Tyr(402) His exchange in domain 7 are not precisely defined. In this study, we show that the Tyr(402) His sequence variation affects Factor H surface recruitment by monomeric C-reactive protein (mCRP) to specific patches on the surface of necrotic retinal pigment epithelial cells. Enhanced attachment of the protective Tyr(402) variants of both Factor H and FHL1 by mCRP results in more efficient complement control and further provides an anti-inflammatory environment. In addition, we demonstrate that mCRP is generated on the surface of necrotic retinal pigment epithelial cells and that this newly formed mCRP colocalizes with the cell damage marker annexin V. Bound to the cell surface, Factor H-mCRP complexes allow complement inactivation and reduce the release of the proinflammatory cytokine TNF-α. This mCRP-mediated complement inhibitory and anti-inflammatory activity at necrotic membrane lesions is affected by residue 402 of Factor H and defines a new role for mCRP, for Factor H, and also for the mCRP-Factor H complex. The increased protective capacity of the Tyr(402) Factor H variant allows better and more efficient clearance and removal of cellular debris and reduces inflammation and pathology.

Oxidative stress and enhanced lipid peroxidation are linked to many chronic inflammatory diseases, including age-related macular degeneration (AMD). AMD is the leading cause of blindness in Western societies, but its aetiology remains largely unknown. Malondialdehyde (MDA) is a common lipid peroxidation product that accumulates in many pathophysiological processes, including AMD. Here we identify complement factor H (CFH) as a major MDA-binding protein that can block both the uptake of MDA-modified proteins by macrophages and MDA-induced proinflammatory effects in vivo in mice. The CFH polymorphism H402, which is strongly associated with AMD, markedly reduces the ability of CFH to bind MDA, indicating a causal link to disease aetiology. Our findings provide important mechanistic insights into innate immune responses to oxidative stress, which may be exploited in the prevention of and therapy for AMD and other chronic inflammatory diseases.

Purpose: To evaluate the efficacy and safety of monthly intravitreal ranibizumab for the treatment of choroidal neovascularizations (CNV) secondary to angioid streaks (AS) in pseudoxanthoma elasticum (PXE)., Design: Twelve-month prospective, open-label, uncontrolled, nonrandomized interventional clinical trial., Methods: In 7 patients, 1 eye with an active CNV was injected with 0.5 mg ranibizumab monthly over 1 year. Distance and reading visual acuity, reading speed, angiographic findings, and central retinal thickness (CRT) on optical coherence tomography were assessed at each visit. Central retinal light increment sensitivity (LIS) was assessed by microperimetry at baseline, at 6 months, and 3 to 4 months after the last injection., Results: Best-corrected visual acuity increased significantly from baseline to month 12 (20/63 or 61 ETDRS letters to 20/32 or 73 ETDRS letters; P = .012). The effect was maintained 3 months later (61 ETDRS letters to 72 ETDRS letters; P = .055). Reading acuity and speed could be maintained throughout the study. Central LIS improved (6.6 dB, SD ± 5.9 at baseline to 7.4 dB, SD ± 6.2 at last follow-up; P < .001). Leakage from active CNVs subsided. Mean change in CRT from baseline to month 12 and 15 was -86 μm (P = .074) and -65 μm (P = .182), respectively. No serious adverse events occurred., Conclusions: Efficacy outcomes indicate a beneficial therapeutic effect of intravitreal ranibizumab on central visual function including retinal LIS. Both the functional and morphologic response based on angiographic and OCT findings to ranibizumab treatment implicate an important pathophysiological role of vascular endothelial growth factor in CNVs secondary to AS in PXE. Intravitreal ranibizumab appears to be a safe and efficacious treatment in these patients., (Copyright © 2011 Elsevier Inc. All rights reserved.)

PURPOSE. To characterize anatomically and functionally the retinal degeneration observed in a transgenic mouse line (OPN1LW-EGFP) expressing enhanced green fluorescent protein (EGFP) in a subpopulation of cone photoreceptors, and to map the location of the transgenic insertion. METHODS. An anatomic comparison of cone survival was carried out between wild type (WT) and transgenic mice at three postnatal time points (P80, P140, and P245). Retinal function was assessed at P245 by ERG and included an ultraviolet flicker stimulus to isolate S-cone function. Chromosomal mapping by FISH and high-resolution mapping on DNA fibers (Fiber-FISH) were performed to identify the location of the transgenic insertion. RESULTS. GFP expression was largely absent in S-cones. Cone numbers were significantly reduced in OPN1LW-EGFP mice at all time points compared to WT, with cone loss independent of GFP expression. Anatomic loss correlated with a functional deficit in dark- and light-adapted ERG responses, including a reduction in UV-flicker response, confirming the degeneration of S-cones. The phenotype of heterozygote mice was slightly less severe than in homozygotes, consistent with a dominantly inherited cone dystrophy. The transgenic insertion mapped to a specific region on chromosome 10 orthologous with loci for progressive bifocal chorioretinal atrophy and North Carolina macular dystrophy on human chromosome 6. CONCLUSIONS. Cone loss is global in OPN1LW-EGFP mice and is independent of GFP expression. The mechanism underlying the degeneration remains elusive; however, disruption of loci associated with dominantly inherited retinal degenerations in humans makes this mouse of great interest.

Purpose: To investigate the long-term effectiveness of intravitreal bevacizumab for treating active choroidal neovascularizations in pseudoxanthoma elasticum (PXE)., Methods: Fourteen patients (16 eyes) received intravitreal bevacizumab (1.5 mg) and were investigated monthly. Further treatments were administered depending on disease activity. Examinations included best-corrected visual acuity, biomicroscopy, optical coherence tomography, fluorescein angiography and indocyanine green angiography, fundus autofluorescence, and digital fundus photography. Areas of atrophy of the retinal pigment epithelium and retinal fibrosis were quantified using semiautomated detection on fundus autofluorescence images., Results: Mean age of the cohort was 55 ± 13 years, and mean best-corrected visual acuity at baseline was 20/80 (logarithm of the minimum angle of resolution, 0.56, SD, 0.51). At last follow-up, after an average of 6.5 ± 5.7 injections over 28 months, best-corrected visual acuity was 20/40 (logarithm of the minimum angle of resolution, 0.31, SD, 0.32; P = 0.04). Central retinal thickness was reduced from 254 ± 45 μm to 214 ± 40 μm (P = 0.035). The size of retinal pigment epithelial atrophy and retinal fibrosis measured on fundus autofluorescence images increased in both the treated eye and the fellow eye (P < 0.05). Best-corrected visual acuity of patients with early disease compared with that of those with advanced disease improved significantly more over the treatment course (20/25 vs. 20/63; P = 0.008)., Conclusion: Intravitreal bevacizumab therapy demonstrates long-term effectiveness by preserving function in advanced disease and improving function in early disease. Best results of treating active choroidal neovascularizations in PXE are achieved when treatment starts the earliest possible.

Purpose: To investigate the efficacy and safety of intravitreal ranibizumab for the treatment of nonproliferative macular telangiectasia (MacTel) type 2., Design: Prospective, open-label, uncontrolled, nonrandomized interventional clinical trial., Methods: One eye (disease stage 2 or 3) of each patient (n = 10) with nonproliferative MacTel type 2 was injected with 0.5 mg ranibizumab at monthly intervals for one year. Visual acuity, angiographic findings, and retinal thickness were assessed at each visit. The primary endpoint was the change in best-corrected distance visual acuity after one year compared to baseline., Results: Mean visual acuity showed a transient increase in the study eye. However, after 12 months of treatment there was no significant change of visual acuity compared to baseline or compared to the fellow eye. Fluorescein angiography revealed a decrease of telangiectatic-appearing capillaries and of late-phase leakage, which was accompanied by a topographically related significant reduction in macular thickness. Three to 5 months after the last treatment, angiographic appearance and retinal thickness were similar to baseline. In one patient, the last intravitreal injection was not performed because of safety concerns after a transitory ischemic attack. Otherwise, no serious adverse events were observed., Conclusions: The angiographic and tomographic effects after intravitreal inhibition of vascular endothelial growth factor (VEGF) using ranibizumab implicate a pathophysiological role of the VEGF pathway in nonproliferative MacTel type 2. As the morphologic response was not associated with a clear functional benefit, and because of the transient nature of the treatment effect, monthly intravitreal ranibizumab is not recommended for the nonproliferative disease stage of MacTel type 2., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Dysregulation of the complement system has been shown to play a major role in the pathogenesis of age-related macular degeneration (AMD)., Methods: The current evidence from human studies derives from immunohistochemical and proteomic studies in donor eyes, genetic association studies, and studies of blood complement protein levels. These lines of evidence are corroborated by in vitro and animal studies., Results: In AMD donor eyes, detection of complement proteins in drusen suggested local inflammatory processes involving the complement system. Moreover, higher levels of complement proteins in the Bruch's membrane/choroid complex could be detected in AMD donor eyes compared to controls. A large number of independent genetic studies have consistently confirmed the association of AMD with risk or protective variants in genes coding for complement proteins, including complement factor H (CFH), CFH-related proteins 1 and 3, factor B/C2, C3 and factor I. Another set of independent studies detected increased levels of complement activation products in plasma of AMD patients, suggesting that AMD may be a systemic disease and the macula a vulnerable anatomic site of minimal resistance to complement activation. Genotype-phenotype correlations, including the impact of genetic variants on disease progression, gene-environment and pharmacogenetic interactions, have been investigated. There is evidence that complement gene variants may be associated with the progression from early to late forms of AMD, whereas they do not appear to play a significant role when late atrophic AMD has already developed. There are indications for an interaction between genetic variants and supplementation and dietary factors. Also, there is some evidence that variants in the CFH gene influence treatment effects in patients with neovascular AMD., Conclusions: Such data suggest that the complement system may have a significant role for developing new prophylactic and therapeutic interventions in AMD. In fact, several compounds acting on the complement pathway are currently in clinical trials. Therapeutics that modulate the complement system need to balance inhibition with preservation of sufficient functional activity in order to maintain adequate immune responses and tissue homeostasis. Specifically, targeting the dysfunction appears more adequate than a global suppression of complement activation in chronic diseases such as AMD.

Indocyanine green (ICG) and fluorescein dyes were inadvertently injected into an antecubital artery during angiography. Apart from a slightly longer arm to retina time, ICG angiography was uneventful. In contrast, intra-arterial injection of fluorescein resulted in a dramatic yellowish discoloration of the arm distal to the injection site that was combined with stinging pain. Fluorescence of both dyes in the forearm could be recorded using a confocal scanning laser ophthalmoscope. The angiographic retinal image quality appeared normal. After about 5 hours, the skin discoloration had disappeared and there were no late complications.

Purpose: To evaluate the clinical relevance of a new diagnostic modality, simultaneous confocal scanning laser ophthalmoscopy (cSLO) and high-speed, high-resolution, spectral-domain optical coherence tomography (OCT), for the visualization of macular pathologies., Methods: OCT images and simultaneous recording of fluorescein angiography, indocyanine green (ICG) angiography, infrared, and blue reflectance ('red-free') or fundus autofluorecence (FAF) images were obtained with a novel imaging device (Spectralis HRA + OCT; Heidelberg Engineering, Heidelberg, Germany). An optically pumped solid-state laser generated the excitation wavelength (488 nm) required for blue reflectance, FAF and fluorescein angiography images. For ICG angiography and infrared imaging, diode laser sources at 790 and 815 nm were used. For OCT, 40 000 A-scans per second were acquired with 7 μm axial and 14 μm lateral optical resolution. The B-scans covering a transversal range of 30° had a scan width up to 1.536 A-scans with a digital lateral resolution of 5 μm/pixel, a scan depth of 1.8 mm with 3.5 μm/pixel digital axial resolution and a scan rate of up to 48 B-scans/second. In addition, volume scans could be obtained at 15, 20 and 30° fields of view. An integrated eye tracking allowed for live averaging of cSLO images as well as OCT B-scans., Results: Early, neovascular and atrophic age-related macular degeneration, macular telangiectasia, retinal arterial, branch vein occlusion and other pathologies were imaged, and cSLO and OCT frames correlated. Fluorescein and ICG angiographic phenomena recorded in cSLO images could be analysed accurately in corresponding OCT cross-sections. Abnormal FAF signals were correlated to alterations at the outer retinal/retinal pigment epithelial cell layer in high-resolution OCT scans. Three-dimensional OCT enabled comprehensive retinal coverage. The imaging software tracked eye movements accurately. Averaging of live B-scans enhanced image quality considerably., Conclusion:   The combined cSLO/OCT system allowed for simultaneous recordings of topographic and tomographic images with accurate correlation between the confocal angiograms, FAF images as well as other imaging modes with the OCT scans. The instrument thus provides simultaneous multi-modal imaging of retinal pathologies and disease., (© 2009 The Authors. Journal compilation © 2009 Acta Ophthalmol.)

Recent imaging studies have suggested that macular pigment is decreased centrally in macular telangiectasia type 2 (MT2). The uptake of xanthophyll pigment into the macula is thought to be facilitated by a xanthophyll-binding protein (XBP). The Pi isoform of glutathione S-transferase (GSTP1) represents one such XBP with high binding affinity. This case-control study aimed to determine whether two common single-nucleotide polymorphisms (SNPs) of GSTP1 were associated with MT2. DNA samples from 39 cases and 21 controls were collected. Two polymorphic sites of Ile105Val and Ala114Val in exons 5 and 6 respectively, of the GSTP1 gene were analysed. Comparison of alleles and genotypes between cases and controls indicated that there were no statistically significant differences for either the Ile105Val SNP (P=0.43) or the Ala114Val SNP (P=0.85), or for any combinations; however, the homozygous at-risk genotype (GG) of the Ile105Val SNP was present in 8% of cases but absent in controls. This study found no statistically significant association between two common GSTP1 SNPs and MT2; however, a trend towards a greater frequency of the GG genotype of the Ile105Val SNP in cases is of great interest. The biological plausibility of disturbed macular pigment uptake in MT2 makes GSTP1 an excellent candidate gene. Further investigation is warranted in future studies of MT2.

Purpose: To analyze focal hyperreflective morphologic alterations in outer retinal layers in patients with type 2 idiopathic macular telangiectasia (MacTel type 2) using spectral-domain optical coherence tomography (SD OCT)., Design: Cross-sectional case-control study., Participants: Forty-one patients with MacTel type 2., Methods: Anatomic layers were evaluated and compared with those of controls of similar age. Simultaneous SD OCT scans were obtained with a combined confocal scanning laser ophthalmoscope for simultaneous tomographic and topographic in vivo imaging (Spectralis HRA+OCT; Heidelberg Engineering, Heidelberg, Germany)., Main Outcome Measures: Morphologic alterations in the retinal layers secondary to MacTel type 2., Results: Hyperreflective spots in the outer retina of MacTel type 2 patients were detected in all stages of disease using the SD OCT. Their presence was confined to the foveolar and parafoveolar region. The phenomenon also was detected in a monozygotic twin in an eye with no typical angiographic sign of the disease. A hyperreflective haze was detected in the vicinity of a disruption of the hyperreflective OCT line that is assumed to represent the line between the photoreceptor inner and outer segments and interdigitation of the outer segments and the retinal pigment epithelium. No corresponding pathologic features could be identified by biomicroscopy, time-domain OCT, or confocal scanning laser ophthalmoscope imaging. Crystalline deposits and intraretinal migration of pigmented cells were distinguishable because of differences in shape, reflectivity, and location., Conclusions: Hyperreflective spots were identified in outer retinal layers of patients with MacTel type 2 in all disease stages. It is suggested that this phenomenon represents an early sign of a neurodegenerative process. Secondary assumptions include extravasated deposits or vascular abnormalities. The pathologic features are indicative of an active disease process before the disease manifests by typical fluorescein angiographic signs., Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references., (Copyright © 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to investigate morphologic differences in a consecutive case series of patients suffering from adult-onset vitelliform macular dystrophy with cuticular drusen (CD) compared with another patient group with a vitelliform lesion only using high-resolution in vivo retinal imaging., Methods: Simultaneous spectral domain optical coherence tomography (870 nm, 40.000 A-scans per second) and confocal scanning laser ophthalmoscopy were performed in 6 patients (12 eyes) with adult-onset vitelliform macular dystrophy using a combined instrument (Spectralis HRA+OCT; Heidelberg Engineering, Heidelberg, Germany)., Results: Mean age was 69 years (59-82 years), and mean visual acuity was 20/80. The vitelliform lesion presented with an accumulation of yellow-gray material with increased fundus autofluorescence. Spectral domain optical coherence tomography imaging showed that the neurosensory detachment was filled with an amorphous homogenously reflective material located between the retinal pigment epithelium and neurosensory retina in the inferior part of the lesion with the superior part being optically empty. The retinal pigment epithelium basal membrane/Bruch membrane band on spectral domain optical coherence tomography showed multiple focal nodules, in analogy to histologic descriptions of CD. Longitudinal observations in a subgroup of patients showed that the vitelliform detachment collapsed with subsequent development of geographic atrophy in patients with CDs., Conclusion: Cuticular drusen may be an indicator for a generalized retinal pigment epithelium dysfunction. High-resolution spectral domain optical coherence tomography allows to image morphologic differences in adult-onset vitelliform macular dystrophy with and without CDs, providing further evidence that adult-onset vitelliform macular dystrophy with CDs represents a separate disease entity.

Background: The impact of retinal pathology detected by high-resolution imaging on vision remains largely unexplored. Therefore, the aim of the study was to achieve high-resolution structure-function correlation of the human macula in vivo., Methodology/principal Findings: To obtain high-resolution tomographic and topographic images of the macula spectral-domain optical coherence tomography (SD-OCT) and confocal scanning laser ophthalmoscopy (cSLO), respectively, were used. Functional mapping of the macula was obtained by using fundus-controlled microperimetry. Custom software allowed for co-registration of the fundus mapped microperimetry coordinates with both SD-OCT and cSLO datasets. The method was applied in a cross-sectional observational study of retinal diseases and in a clinical trial investigating the effectiveness of intravitreal ranibizumab in macular telangietasia type 2. There was a significant relationship between outer retinal thickness and retinal sensitivity (p<0.001) and neurodegeneration leaving less than about 50 µm of parafoveal outer retinal thickness completely abolished light sensitivity. In contrast, functional preservation was found if neurodegeneration spared the photoreceptors, but caused quite extensive disruption of the inner retina. Longitudinal data revealed that small lesions affecting the photoreceptor layer typically precede functional detection but later cause severe loss of light sensitivity. Ranibizumab was shown to be ineffective to prevent such functional loss in macular telangietasia type 2., Conclusions/significance: Since there is a general need for efficient monitoring of the effectiveness of therapy in neurodegenerative diseases of the retina and since SD-OCT imaging is becoming more widely available, surrogate endpoints derived from such structure-function correlation may become highly relevant in future clinical trials.

Purpose: To investigate, with the use of spectral-domain optical coherence tomography (SD-OCT), microstructural alterations over time in eyes with progressive geographic atrophy (GA) due to age-related macular degeneration., Methods: Forty-six eyes of 26 patients (median age, 77.9 years [interquartile range (IQR), 71.8-81.0]) with GA without evidence of active or previous neovascular disease at baseline were examined by simultaneous confocal scanning laser ophthalmoscopy (cSLO) and SD-OCT. Serial examinations with alignment of follow-up to baseline scans were performed over a median period of 12.2 months (IQR, 10.2-15.3). Longitudinal SD-OCT variations were evaluated, including quantification of retinal thickness (RT) change and lateral spread of GA (LSGA) at a temporal, nasal, inferior, and superior GA border-section in each eye., Results: GA-enlargement was characterized by progressive loss of the outer hyperreflective SD-OCT bands and by thinning of the outer nuclear layer with subsequent approach of the outer plexiform layer toward Bruch's membrane. In the perilesional zone, various dynamic changes were recorded, including migration of hyperreflective material and changes in drusen height. At the borders, there was a median RT change of -14.09 microm/y (IQR -26.21 to -7.48 microm/y). The median LSGA was 106.90 microm/y (IQR, 55.44-161.70 microm/y). Both parameters showed only moderate intraocular agreement (RT change: intraclass correlation coefficient [ICC], 0.54; 95% CI, 0.39-0.67; LSGA: ICC, 0.49; 95% CI, 0.34-0.64) and no statistical significant difference for one location (RT change, P = 0.125; LSGA, P = 0.516; likelihood ratio test)., Conclusions: Combined cSLO and SD-OCT imaging provides unprecedented insight into dynamic microstructural changes of GA enlargement that may help to better understand the pathogenesis of the disease. Quantitative progression data indicate local factors may exist that drive progression in junctional areas (ClinicalTrials.gov number, NCT00393692).

Purpose: To investigate the Bruch's membrane-retinal pigment epithelium (RPE) complex in pseudoxanthoma elasticum (PXE) by imaging techniques capable of visualizing deep retinal structures with high contrast., Design: Prospective cross-sectional study., Participants: Patients with PXE, confirmed by mutation analysis, skin histopathologic examination, or both., Methods: Sixteen patients were investigated by indocyanine green (ICG) and fluorescein angiography, confocal near-infrared (NIR) reflectance, and fundus autofluorescence imaging using a confocal scanning laser ophthalmoscope (Spectralis HRA-OCT; Heidelberg Engineering, Heidelberg, Germany). Composite digital fundus photography also was performed., Main Outcome Measures: Characterization and topographic distribution of abnormalities detected by retinal imaging., Results: On late-phase ICG angiography, a central area of decreased fluorescence centered on the posterior pole was a characteristic finding in all patients. A second area characterized by increased fundus reflectivity on NIR reflectance imaging extended further into the periphery. A third and most eccentric area showed neither decreased ICG fluorescence nor increased fundus reflectivity. These 3 areas were separated by 2 transition zones, the second being the equivalent of peau d'orange. Angioid streaks did not extend into the third area., Conclusions: The abnormalities detected by this multimodal imaging approach suggest a centrifugal spread of the retinal pathologic features of the Bruch's membrane-RPE complex in PXE. Decreased fluorescence on late-phase ICG angiography is a consistent sign of retinal pathologic features in PXE. Bruch's membrane calcification may be the underlying cause for the increased reflectivity observed on NIR reflectance imaging., Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references., (Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to establish and evaluate a nationwide telephone counseling for patients with retinal diseases hotline in Germany against the background of an increasing demand for information and counseling in the field of retina services as a result of current demographic trends., Methods: The telephone Retina Hotline was installed, advertised, and run for 1.5 years at the Department of Ophthalmology, University of Bonn, and open to callers from the whole of Germany. The hotline was staffed by ophthalmologists. Calls were handled according to standard flow charts and counsel given adhered to a list of standardized answers as appropriate in the individual case. All calls were documented in an online database, which was subsequently analyzed and used for evaluation., Results: A total of 1,384 calls were documented leading to an average of 7.6 calls per afternoon. The average length of calls was 8.5 minutes. The majority of callers were female patients (63%) who had age-related macular degeneration. Only 17% of callers were relatives. Most callers (59%) were >60 years of age. The majority of questions were related to therapeutic options for dry or neovascular age-related macular degeneration as well as various forms of retinitis pigmentosa (45%)., Conclusion: A service such as the Retina Hotline seems necessary and well justified against the background of need for information and support documented. However, on the basis of an adequate computer program and a standard catalog of answers or flow charts, it may not need to be staffed by ophthalmologists, but well-trained nonmedical staff may be sufficient.

Various morphological and functional techniques for retina examination have been established in the recent years. Although many examination results are spatially resolved and can be mapped onto data originating from other modalities, usually only data from one modality is analyzed by a clinician at a time. This is mainly because there is no software available to the public that enables the registration of structure and function in the clinical setting. Therefore we developed an integrated mapping application that allows the registration and analysis of morphological data (fundus photography, optical coherence tomography, scanning laser ophthalmoscopy images, and GDx thickness profiles) and functional data (multifocal electroretinography, multifocal pattern electroretinography, perimetry, and microperimetry). To obtain quantitative data that can be used for clinical trials and statistical analyses, extraction routines for morphological parameters - such as retinal layer thicknesses and measures of the vascular network - have been integrated. Global, regional and point-specific data from registered modalities can be extracted and exported for statistical analyses. In this article we present the implementation and examples of use of the developed software.

Activation of the alternative pathway of complement is implicated in common neurodegenerative diseases including age-related macular degeneration (AMD). We explored the impact of common variation in genes encoding proteins of the alternative pathway on complement activation in human blood and in AMD. Genetic variation across the genes encoding complement factor H (CFH), factor B (CFB) and component 3 (C3) was determined. The influence of common haplotypes defining transcriptional and translational units on complement activation in blood was determined in a quantitative genomic association study. Individual haplotypes in CFH and CFB were associated with distinct and novel effects on plasma levels of precursors, regulators and activation products of the alternative pathway of complement in human blood. Further, genetic variation in CFH thought to influence cell surface regulation of complement did not alter plasma complement levels in human blood. Plasma markers of chronic activation (split-products Ba and C3d) and an activating enzyme (factor D) were elevated in AMD subjects. Most of the elevation in AMD was accounted for by the genetic variation controlling complement activation in human blood. Activation of the alternative pathway of complement in blood is under genetic control and increases with age. The genetic variation associated with increased activation of complement in human blood also increased the risk of AMD. Our data are consistent with a disease model in which genetic variation in the complement system increases the risk of AMD by a combination of systemic complement activation and abnormal regulation of complement activation in local tissues.

Purpose: To investigate the value of multimodal confocal scanning laser ophthalmoscopy (cSLO) for phenotyping fundus lesions in patients with pseudoxanthoma elasticum (PXE) and to correlate these findings with morphologic alterations detected by spectral domain optical coherence tomography (SD-OCT)., Methods: Imaging was performed with a combined SD-OCT-cSLO system (Spectralis HRA-OCT; Heidelberg Engineering, Heidelberg, Germany). OCT scans were placed at locations of interest on near-infrared (NIR) reflectance, fundus autofluorescence (FAF), and fluorescein angiography (FA) images. The instrument allowed for exact topographic correlation of findings on OCT and cSLO images., Results: NIR reflectance imaging showed the highest sensitivity to detect angioid streaks and peau d'orange compared to FAF or FA. On OCT scans, angioid streaks reliably showed breaks in Bruch's membrane. Peau d'orange was associated with alternating reflectivity within Bruch's membrane. Characteristic mid-peripheral chorioretinal atrophies showed hyporeflective spaces involving the outer neurosensory retina. In eyes with pattern dystrophy like alterations, subneurosensory accumulation of material was observed within areas of increased FAF., Conclusions: SD-OCT in combination with cSLO imaging using NIR light locates the primary pathologic formations of angioid streaks and peau d'orange in Bruch's membrane. NIR reflectance imaging may be superior for detecting PXE-related fundus lesions at the level of Bruch's membrane, because the blue laser light that is used in FAF and FA is markedly absorbed by the pigment epithelium and therefore may only detect alterations if this cell layer is also affected. The findings indicate that multimodal cSLO and SD-OCT imaging of the outer retina allows for screening of PXE related retinal alterations.

Objective: To report findings in asymptomatic family members of patients with macular telangiectasia type 2., Design: Prospective, observational, cross-sectional case series., Participants: Four patients with symptomatic macular telangiectasia type 2 (index patients) and 5 relatives, including 2 sets of monozygotic twins., Methods: Screening of family members of participants in a non-interventional natural history study of macular telangiectasia type 2. Ophthalmologic examination included best-corrected visual acuity testing, fundus biomicroscopy, fluorescein angiography (FA), optical coherence tomography (OCT), and fundus autofluorescence (FAF) imaging., Main Outcome Measures: Evidence for macular telangiectasia type 2 in any of the imaging methods used and visual function of the family members studied., Results: In the first family, 2 of 3 daughters of a severely affected 68-year-old woman had features of macular telangiectasia type 2. Although one of the daughters was diagnosed by biomicroscopic examination, the second daughter was diagnosed only by subtle changes on OCT and FAF imaging. Both affected daughters were asymptomatic and were unaware that they had the condition. In the second family, clinical examination showed that the 60-year-old brother of the 75-year-old index patient obviously was affected, despite a lack of any subjective visual dysfunction. The 65-year-old monozygotic twin of the third index patient showed a slight retinal thinning within a small area temporal to the foveola in both eyes as well as minor staining on FA and a subtle monocular loss of macular pigment. The 56-year-old asymptomatic monozygotic twin of the last proband had opacification of the retina with leakage on FA in the right eye. The fellow eye was unremarkable except for an abnormal FAF signal that was present in both eyes., Conclusions: Macular telangiectasia type 2 may be more common than previously assumed, but patients may not seek ophthalmic care if their visual function is normal. The study of these early, asymptomatic cases may yield valuable insights into the pathogenesis of the condition. Further research is warranted to determine whether there is an underlying, dominantly inherited genetic abnormality in macular telangiectasia type 2 of variable penetrance and expressivity.

Purpose: Pseudoxanthoma elasticum (PXE) is an inherited multisystem disorder of the elastic tissue. Typical ocular manifestations include angioid streaks, peau d'orange, salmon spots, and choroidal neovascularization (CNV). Changes in Bruch membrane lead to progressive atrophy of the retinal pigment epithelium (RPE), secondary CNVs, and visual loss. The RPE-photoreceptor complex was studied in vivo using fundus autofluorescence (FAF) imaging., Methods: Forty-six patients (92 eyes) with PXE were investigated using digital fundus photography, fluorescein angiography (FA), and FAF imaging. The diagnosis was confirmed by multisystem clinical examination, mutation analysis of the ABCC6 gene, and skin biopsy., Results: The mean age of the patient cohort was 50 years (range, 13-74 years), and mean visual acuity was 20/125. Fundus changes typical for PXE were observed in all eyes. Angioid streaks were detected in all but six eyes. Peau d'orange was hardly detectable on FAF, whereas comet tail lesions were apparent. Retinal pigment epithelium atrophy typically was widespread and heterogeneous, located mostly adjacent to angioid streaks or CNVs. Pattern dystrophy-like changes were only found in patients with previous CNV formation in the same or the contralateral eye., Conclusion: Abnormalities of the RPE-photoreceptor complex detected by FAF imaging were more diverse and widespread than expected from conventional fundus imaging. The exhibition of pattern dystrophy-like changes may be a transitional state toward a neovascular event in a subgroup of patients. The extensive alteration of the RPE suggests an important role of pathologic RPE changes in the evolution of visual loss in PXE.

Purpose: To assess metamorphopsia in patients with macular telangiectasia (MacTel) type 2., Methods: In a prospective observational cohort study, 40 eyes of 20 patients with MacTel type 2 were investigated by funduscopy, fluorescein angiography, optical coherence tomography and microperimetry. Metamorphopsia was assessed using Amsler grids following a standard protocol and standardized questionnaire., Results: Metamorphopsia was present in 30 (83%) out of 36 nonproliferative eyes and in all four eyes with neovascular membranes. In the 30 nonproliferative eyes with distortions, metamorphopsia was always present in the nasal quadrant of the central visual field. Distortions were most pronounced in the nasal and lower quadrant in 70 and 30%, respectively. Three nonproliferative eyes with a very early and three eyes with a late disease stage did not perceive metamorphopsia. The degree of distortions was often but not necessarily correlated with the degree of leakage. Metamorphopsia was present in five out of eight eyes with normal sensitivity in microperimetry testing. Detection of scotoma by Amsler grid testing was poor., Conclusion: Metamorphopsia is a frequent clinical symptom in MacTel type 2 even in the absence of neovascularization. Since macular thickness was within normal limits in such eyes, extensive swelling or distortion of the neurosensory retina would not account for metamorphopsia in contrast to other macular diseases such as age-related macular degeneration or idiopathic epiretinal membranes.

A 44-year-old male patient first noticed a pain-free light red swelling of the right eye in 1983. Based on the results of the early indocyanine green angiography, MRI and sonography, a racemose hemangioma of the conjunctiva was diagnosed. Although a racemose hemangioma already exists at birth, it remains clinically silent for a long time and symptoms often first appear in early adulthood. In this patient external surgical excision was terminated due to substantial bleeding. A symptomatic treatment in the sense of surface care is considered to be the best option.

Purpose: To investigate morphologic alterations in geographic atrophy caused by age-related macular degeneration (AMD) in the presence of foveal sparing using high-resolution in vivo imaging., Methods: Simultaneous spectral domain optical coherence tomography (SD-OCT, 870 nm, 40,000 A-scans/s) and confocal scanning laser ophthalmoscopy (cSLO; fundus autofluorescence; excitation, 488 nm; emission, 500-700 nm) were performed in 18 eyes with geographic atrophy and foveal sparing using a combined instrument. Anatomic layers were evaluated, and retinal thickness in the fovea and the peripheral macula were measured and compared with those in controls of similar age., Results: Fundus autofluorescence imaging showed an inhomogeneously reduced signal at the residual foveal island. SD-OCT scans disclosed mitigation of the foveal pit in the absence of extracellular fluid accumulation and an increased mean central retinal thickness of 248 +/- 28 microm compared with 225 +/- 12 microm in control eyes (P = 0.005). No difference in retinal thickness in the peripheral macula was observed (245 +/- 16 vs. 253 +/- 11 microm; P = 0.6). Subanalysis revealed marked appearance of swelling and widening of visible structures at the central outer nuclear layer (153 +/- 22 microm vs. 127 +/- 12 microm; P = 0.003). Below the external limiting membrane, a broad band of irregular high reflectivity was detected instead of the normal three separate reflective bands., Conclusions: Thickening at the foveal site may reflect a pre-apoptotic stage of neuronal cellular elements indicating imminent atrophy. Limited structure-function correlation found in our study suggests that future therapeutic intervention may be beneficial in only a subset of AMD patients with foveal sparing.

Aim: To characterise the ocular phenotype of a family segregating the splice site mutation c.2189+1G>T in the tyrosine kinase receptor gene MERTK., Methods: Five affected children of a consanguineous Moroccan family were investigated by ophthalmic examinations, including fundus photography, autofluorescence (FAF) imaging, optical coherence tomography (OCT), psychophysical and electrophysiological methods., Results: Affected children were between 5 and 19 years of age, allowing an estimation of disease progression. Electroretinography demonstrated loss of scotopic and photopic function in the first decade of life. Younger siblings showed drusen-like deposits with focal relatively increased FAF in the macular area. With increasing age, a yellowish lesion with relatively increased FAF and subsequent macular atrophy developed. Visual acuity deteriorated with age and ranged between 20/50 in the best eye of the youngest affected and 20/400 in the worst eye of the oldest affected sibling. Spectral-domain OCT revealed debris-like material in the subneurosensory space., Conclusion: The splice site mutation c.2189+1G>T in MERTK causes rod-cone dystrophy with a distinct macular phenotype. The debris in the subneurosensory space resembles that in the Royal College of Surgeons (RCS) rat being the mertk animal model. Patients might therefore benefit from advances in gene therapy that were previously achieved in the RCS rat.

Recently, a unique distribution, namely a reduction of macular pigment optical density (MPOD) within the central retina with a surrounding ring-like structure of preserved MPOD at about 6 degrees eccentricity was suggested to be a common finding in macular telangiectasia (MacTel) type 2. In order to quantify this reduced MPOD, 28 eyes of 14 patients with MacTel type 2 were investigated by fundus reflectometry and two wavelengths fundus autofluorescence (FAF; at 488 nm and 514 nm). Fundus reflectometry showed a reduced MPOD within the central 4 degrees eccentricity that was most absent temporal to the foveola. At 6 degrees, MP density was not different from normative values. Two wavelengths FAF was in accordance with these findings. Fundus reflectometry also allowed separate determination of lutein and zeaxanthin. The patients with MacTel type 2 showed a disproportionally high zeaxanthin reduction. The study suggests that in MacTel type 2, there might be an inability to accumulate MP in the central retina. This disease might serve as a model to further study abnormalities of MP distribution in retinal disorders and to elucidate the mechanisms of MP deposition in the retina.

Purpose: To describe the occurrence of discrete arcs of increased fundus autofluorescence (FAF) associated with various retinal dystrophies and to assess their functional significance by fundus-controlled microperimetry., Methods: Seven patients, three with pigmented paravenous retinochoroidal atrophy (PPRCA), one with sector retinitis pigmentosa (RP), one with typical RP, and two with macular dystrophy were assessed by retinal imaging including FAF imaging. Serial images were obtained within a review period of 6 and 10 years in a patient with PPRCA and macular dystrophy, respectively. Fundus-controlled microperimetry was performed in eight eyes of five patients to determine light increment sensitivity., Results: A discrete arched line of increased FAF was observed without obvious correlate on fundus biomicroscopy. The orientation of this line differed from ring shape in RP and macular dystrophy, a semi-circle structure in sector RP to crescent shape with tiplike extensions towards branching retinal veins in PPRCA. Longitudinal investigation revealed slight migration of the arc in PPRCA and peripheral extension of the ring diameter in macular dystrophy. Microperimetry revealed that the arc of increased FAF sharply delineated areas of severely impaired retinal sensitivity., Conclusions: The findings indicate that arcs of increased FAF in PPRCA and other retinal dystrophies demarcate areas of impaired retinal function and may migrate over time. FAF imaging may therefore reveal the exact extent of neurosensory dysfunction that may exceed the dimensions anticipated by conventional examinations.

Pseudoxanthoma elasticum (PXE) is an inherited disorder that is associated with accumulation of mineralized and fragmented elastic fibers in the skin, vascular walls, and Bruch's membrane in the eye. Clinically, patients exhibit characteristic lesions of the posterior segment of the eye including peau d'orange, angioid streaks, and choroidal neovascularisations, of the skin including soft, ivory-colored papules in a reticular pattern that predominantly affect the neck and large flexor surfaces, and of the cardiovascular system with peripheral and coronary arterial occlusive disease as well as gastrointestinal bleedings. There is yet no definitive therapy. Recent studies suggest that PXE is inherited almost exclusively as an autosomal recessive trait. Its prevalence has been estimated to be 1:25,000-100,000. Very recently, the ABCC6 gene on chromosome 16p13.1 was found to be associated with the disease. Mutations within ABCC6 cause reduced or absent transmembraneous transport that leads to accumulation of extracellular material. Presumably, this mechanism causes calcification of elastic fibers. Despite the characteristic clinical features, the variability in phenotypic expressions, and the low prevalence may be responsible for the disease being underdiagnosed. This review compiles and summarizes current knowledge of PXE pathogenesis and clinical findings. Furthermore, different therapeutic strategies to treat retinal manifestations are discussed, including thermal laser coagulation, photodynamic therapy, and intravitreal injections of drugs inhibiting vascular endothelial growth factor.