Macular Degeneration: Holz FG

Bellmann C, Unnebrink K, Rubin GS, Miller D, Holz FG. · Department of Ophthalmology, University of Heidelberg, INF 400, 69120 Heidelberg, Germany. · Graefes Arch Clin Exp Ophthalmol. · Pubmed #13680248 No free full text.

Abstract: BACKGROUND: Patients with advanced age-related macular degeneration (AMD) suffer not only from impairment in central visual acuity (VA), but also from reduction in contrast sensitivity (CS). We examined VA and CS changes over time in patients with subfoveal choroidal neovascularizations (CNV) as well as the correlation between the two parameters. METHODS: VA was determined according to a standardized protocol with the Early Treatment Diabetic Retinopathy (ETDRS) chart. CS was measured with Pelli-Robson charts. The angiographic characteristics of CNV and the presence of CNV in the fellow eye as well as gender and age were evaluated as possible prognostic factors of VA and CS progression. Two hundred and five patients with neovascular AMD were recruited within the Radiation Therapy for Age-Related Macular Degeneration (RAD) Study and were reviewed over 2 years. The treatment and control groups showed no significant difference for VA or for CS ( P>0.05), and both groups were considered together. RESULTS: At baseline, mean VA was 55.6+/-14.5 SD letters (EDTRS chart), and mean CS was 22.8+/-6.9 letters (Pelli-Robson chart). Spearman Correlation Coefficient ( r(s)) between VA and CS was r(s)=0.60, P=0.0001. Over 2 years the mean VA loss was 23.6+/-21.4 letters and mean CS reduction was 9.0+/-9.7 letters. Agreement between change of VA and change of CS was moderate ( r(s)=0.65, P=0.0001; kappa coefficient (grouped into VA loss < or =15, >15, >30 letters; CS loss < or =6, >6, >15 letters) kappa=0.43, 95% CI [0.32;0.54]). Proportional hazard models did not show any apparent influence of type of CNV, or CNV in the fellow eye, on change in VA and CS. CONCLUSION: The results indicate that VA and CS do not always show the same progression in visual function loss although they show a moderate correlation in eyes with neovascular AMD. Both parameters provide important information about visual disability and should be evaluated as outcome in interventional studies.

Holz FG, Jorzik J, Schutt F, Flach U, Unnebrink K. · Department of Ophthalmology, University of Heidelberg, Im Neuenheimer Feld 400, D-69120 Heidelberg, Germany. · Ophthalmology. · Pubmed #12578787 No free full text.

Abstract: OBJECTIVE: To determine intraobserver and interobserver variation for classifying types of choroidal neovascularizations (CNV) in exudative age-related macular degeneration (ARMD). DESIGN: Intraexaminer and interexaminer reliability study. PARTICIPANTS: Digital high-quality fluorescein angiograms of 40 patients with neovascular ARMD were evaluated independently by 16 retinal specialists. MAIN OUTCOME MEASURES: Fluorescein angiographies were presented in two randomized sequences (series A and B) to each masked reader for classification of type of CNV into classic, occult, or mixed with classic component of less or greater 50%. Agreement was evaluated by calculating kappa statistics (kappa) and intraclass correlation coefficients. RESULTS: The mean kappa coefficient was 0.64 +/- 0.11 for intraobserver variation, with a range from 0.44 to 0.89. For interobserver variation the intraclass correlation coefficients was calculated as 0.66 (95% confidence interval [CI] 0.56, 0.77) for series A and as 0.55 (95% CI 0.43, 0.67) for series B. CONCLUSIONS: Angiographic classification of CNV secondary to ARMD can vary considerably not only between observers but also for repeated evaluation by the same observer. Because various current and emerging treatments including photodynamic therapy are based on specific angiographic characteristics, accurate interpretation will become more important.

Schmitz-Valckenberg S, Jorzik J, Unnebrink K, Holz FG, Anonymous00191. · Department of Ophthalmology, University of Heidelberg, Germany. · Graefes Arch Clin Exp Ophthalmol. · Pubmed #11933894 No free full text.

Abstract: BACKGROUND: Fundus autofluorescence (AF) imaging using confocal scanning laser ophthalmoscopy (cSLO) has been shown to be superior to fundus photography or angiography for delineating areas of geographic atrophy (GA) in retinal pigment epithelium (RPE) and for recording variation over time. We have evaluated a method for automated computerized detection and quantitation of RPE atrophy. METHODS: AF images in vivo were recorded with a confocal scanning laser ophthalmoscope (exc. 488 nm, em. >500 nm; Heidelberg Retina Angiograph). The intensity of AF in atrophic areas was markedly decreased. Two independent readers analysed these areas in 24 right eyes manually by outlining GA areas using a mouse-driven arrow (method A) and automatically by image analysis software (Global Lab Image/2) after subjective adjustment of thresholding (method B). Agreement between observers and between methods A and B was assessed by the Bland-Altman design for method-comparison studies. RESULTS: Larger areas were measured using method A than B by both readers (agreement A/B: reader 1 mean difference 1.04 mm, 95% CI [0.66,1.42]; reader 2 mean difference 0.62 mm, 95% CI [0.43,0.81]). The agreement between the readers was mean difference 0.39 mm (95% CI [0.02,0.76]) for A and mean difference -0.03 mm (95% CI [-0.23,0.18]) for B. Features making the delineation of borders of GA difficult included large choroidal vessels with autofluorescent properties in the GA area and media opacities. CONCLUSIONS: Fundus AF cSLO imaging provides a reliable means to delineate areas of GA. The automated image analysis allows more accurate detection and quantitative documentation of atrophic areas than manual outlining. This method will be useful in longitudinal natural history studies and for monitoring effects of future therapeutic interventions to slow down GA progression in patients with advanced atrophic ARMD and other retinal diseases associated with outer retinal atrophy.

Krohne TU, Hunt S, Holz FG. · Department of Ophthalmology, University of Bonn, Ernst-Abbe-Str. 2, D-53127 Bonn, Germany. · Br J Ophthalmol. · Pubmed #18952645 No free full text.

Abstract: BACKGROUND: Translocation of an autologous retinal pigment epithelium (RPE) sheet under the macula is currently under investigation as a treatment for exudative AMD. Excimer laser-assisted RPE sheet translocation (EST) employs intraocular excimer ablation of excess graft choroidal tissue as a measure to enhance RPE sheet functionality. This study assessed potential adverse effects of excimer irradiation on RPE cells in vitro. METHODS: Human RPE cells (ARPE-19) received 308 nm XeCl excimer laser treatment or 311-312 nm UV-B irradiation. Cell death was visualised with Trypan Blue and quantified by LDH release assay. Apoptosis was detected by DNA fragmentation assay. RESULTS: Laser treatment of 0.175-0.25 J/cm(2) resulted in delayed cell death within 48 h. Time course and dose response paralleled the effect of UV-B irradiation. Cytotoxicity was mediated by apoptosis. Human choroid/Bruch membrane tissue sheets covering the cells during laser irradiation reduced cytotoxicity by 87-95%. CONCLUSION: Cultured human RPE cells are susceptible to apoptotic cell death induced by 308 nm excimer laser irradiation. Absorption by choroid/Bruch membrane tissue can largely prevent the cytotoxic effect. In clinical application, the residual adverse effect of laser ablation on graft RPE cell viability needs to be outweighed by potential advantageous effects on graft survival and functionality to allow for a sensible application of excimer ablation in RPE translocation surgery.

Fleckenstein M, Charbel Issa P, Helb HM, Schmitz-Valckenberg S, Scholl HP, Holz FG. · Department of Ophthalmology, University of Bonn, Bonn, Germany. · Arch Ophthalmol. · Pubmed #18852430 No free full text.

This publication has no abstract.

Krohne TU, Eter N, Holz FG, Meyer CH. · Department of Ophthalmology, University of Bonn, Bonn, Germany. · Am J Ophthalmol. · Pubmed #18635152 No free full text.

Abstract: PURPOSE: To investigate intraocular concentrations and pharmacokinetics of bevacizumab after a single intravitreal injection in humans. DESIGN: Prospective, noncomparative, interventional case series. METHODS: We included 30 nonvitrectomized eyes of 30 patients (age range, 43 to 93 years) diagnosed with clinically significant cataract and concurrent macular edema secondary to neovascular age-related macular degeneration, diabetic retinopathy, or retinal venous occlusion in the same eye. All patients received an intravitreal injection of 1.5 mg bevacizumab. Between one and 53 days after injection, an aqueous humor sample was obtained during elective cataract surgery. Concentrations of unbound bevacizumab in these samples were quantified by enzyme-linked immunosorbent assay. RESULTS: Concentration of bevacizumab in aqueous humor peaked on the first day after injection with a mean concentration (c(max)) of 33.3 microg/ml (range, 16.6 to 42.5 microg/ml) and subsequently declined in a monoexponential fashion. Nonlinear regression analysis determined an elimination half-time (t(1/2)) of 9.82 days (R(2) = 0.81). No significant differences between diagnosis subgroups were noted. CONCLUSIONS: In human nonvitrectomized eyes, the aqueous half-life of 1.5 mg intravitreally injected bevacizumab is 9.82 days.

Scholl HP, Charbel Issa P, Walier M, Janzer S, Pollok-Kopp B, Börncke F, Fritsche LG, Chong NV, Fimmers R, Wienker T, Holz FG, Weber BH, Oppermann M. · Department of Ophthalmology, University of Bonn, Bonn, Germany. · PLoS One. · Pubmed #18596911 links to  free full text

Abstract: Dysregulation of the alternative pathway (AP) of complement cascade has been implicated in the pathogenesis of age-related macular degeneration (AMD), the leading cause of blindness in the elderly. To further test the hypothesis that defective control of complement activation underlies AMD, parameters of complement activation in blood plasma were determined together with disease-associated genetic markers in AMD patients. Plasma concentrations of activation products C3d, Ba, C3a, C5a, SC5b-9, substrate proteins C3, C4, factor B and regulators factor H and factor D were quantified in patients (n = 112) and controls (n = 67). Subjects were analyzed for single nucleotide polymorphisms in factor H (CFH), factor B-C2 (BF-C2) and complement C3 (C3) genes which were previously found to be associated with AMD. All activation products, especially markers of chronic complement activation Ba and C3d (p<0.001), were significantly elevated in AMD patients compared to controls. Similar alterations were observed in factor D, but not in C3, C4 or factor H. Logistic regression analysis revealed better discriminative accuracy of a model that is based only on complement activation markers Ba, C3d and factor D compared to a model based on genetic markers of the complement system within our study population. In both the controls' and AMD patients' group, the protein markers of complement activation were correlated with CFH haplotypes.This study is the first to show systemic complement activation in AMD patients. This suggests that AMD is a systemic disease with local disease manifestation at the ageing macula. Furthermore, the data provide evidence for an association of systemic activation of the alternative complement pathway with genetic variants of CFH that were previously linked to AMD susceptibility.

Schmitz-Valckenberg S, Fleckenstein M, Göbel AP, Sehmi K, Fitzke FW, Holz FG, Tufail A. · Department of Ophthalmology, University of Bonn, Bonn, Germany. · Am J Ophthalmol. · Pubmed #18514607 No free full text.

Abstract: PURPOSE: To compare fundus autofluorescence images (FAF) between a modified fundus camera (mFC) and a confocal scanning laser ophthalmoscope (cSLO). DESIGN: Evaluation of diagnostic technology. METHODS: Thirty-two eyes of 16 patients with age-related geographic atrophy (GA) treated in an institutional setting were included. FAF images were obtained with both the cSLO (excitation, 488 nm; emission, > 500 nm) and the mFC (excitation, approximately 500 to 610 nm; emission, approximately 675 to 715 nm). Using established algorithms, images were graded by two independent observers and agreements were evaluated. The main outcome measures were image quality, quantification of total atrophy, and classification of FAF patterns. RESULTS: In two eyes with advanced cataract (lens grade 7 according to the Age-Related Eye Disease Study classification), FAF image quality with both systems was not sufficient for any meaningful analysis. In the remaining 30 eyes, the mean differences of the interobserver agreements for atrophy quantification were 0.16 mm2 (95% confidence interval [CI], 0.07 to 0.38) for mFC and 0.15 mm2 (95% CI, -0.04 to 0.33) for cSLO images. Because of inferior signal-to-noise ratios, FAF pattern classification was possible in a lower number of mFC images (69%) compared with cSLO images (88%). CONCLUSIONS: This study suggests that the agreements for atrophy quantification are similar with both devices. The lesser visualization of FAF patterns with the mFC and thus inferior determination of disease markers may be the result of the nonconfocality and the use of single instead of mean images compared with the cSLO. These findings may be important for the design of interventional trials as well as the routine use of FAF imaging in age-related geographic atrophy.

Fleckenstein M, Charbel Issa P, Helb HM, Schmitz-Valckenberg S, Finger RP, Scholl HP, Loeffler KU, Holz FG. · Department of Ophthalmology, University of Bonn, Bonn, Germany. · Invest Ophthalmol Vis Sci. · Pubmed #18487363 No free full text.

Abstract: PURPOSE: To describe morphologic variations in outer retinal layers in eyes with atrophic age-related macular degeneration (AMD) using high-resolution, spectral-domain optical coherence tomography (SD-OCT). METHODS: SD-OCT scans were obtained with a combined confocal scanning laser ophthalmoscope (cSLO) and SD-OCT for simultaneous tomographic and topographic in vivo imaging. A total of 81 eyes of 56 patients (mean age, 77.8 +/- 7.4 years) with geographic atrophy (GA) were examined. Morphologic alterations were analyzed and classified in the perilesional zone, at the junction between GA and nonatrophic retina, and in the atrophic area itself. RESULTS: In the perilesional zone, distinct morphologic alterations included elevations of the outer retinal layers, thickening, and spikes of the outer hyperreflective band as well as clumps at different neurosensory retinal levels. At the junction, highly variable transitions of the outer retinal layers were present with different degrees of loss of the normal hyperreflective bands. Within the actual GA, hyperreflective clumps at different retinal levels, segmented plaques of the outer band and elevations with variable reflectivity were visualized. CONCLUSIONS: SD-OCT imaging in eyes with GA revealed a wide spectrum of morphologic alterations, both in the surrounding retinal tissue and in the atrophic area. These alterations may reflect different disease stages or, alternatively, heterogeneity on a cellular and molecular level. Longitudinal studies using in vivo SD-OCT imaging may allow evaluation of the relevance of these phenotypic changes as potential predictive markers for the progression of disease (i.e., enlargement rates of GA over time) and may be used for monitoring of future therapeutic interventions.

Finger RP, Fleckenstein M, Holz FG, Scholl HP. · Department of Ophthalmology, University of Bonn, Bonn, Germany. · Qual Life Res. · Pubmed #18365767 No free full text.

Abstract: PURPOSE: Age-related macular degeneration (AMD) has a considerable impact on older adults' independence and autonomy. Recently, patient reported outcomes (PROs) such as QoL have been met with increasing interest by the scientific community, healthcare payers and planners. Against this background, the multitude of psychometric tools used to measure QoL in AMD was reviewed. METHODS: A search of the literature from 1990 onwards yielded 355 results, out of which 58 publications were included in the review. Data regarding design, validation and extent of utilization were obtained where available. RESULTS: The National Eye Institute-Visual Function Questionnaire (NEI VFQ-25-item) was found to be the most often used (29% of studies) and best validated psychometric tool, followed by the Visual Function Questionnaire (VF-14; 17%), and the Impact of Vision Impairment Profile (IVI; 9%). Most tools that were identified have been validated for the use in AMD patients. CONCLUSION: Psychometric tools specifically designed to measure vision-related quality of life are well equipped and validated to measure QoL in AMD. More recent developments such as the Macular Disease-dependent Quality of Life (MacDQoL) questionnaire might be able to depict dimensions of vision-related QoL in greater depth. Future studies should endeavour to use a suggested standard when gathering data on vision related QoL, allowing for international comparisons.

Meyer CH, Scholl HP, Eter N, Helb HM, Holz FG. · Department of Ophthalmology, University of Bonn, Germany. · Acta Ophthalmol. · Pubmed #18221499 No free full text.

Abstract: PURPOSE: To assess the effectiveness of consecutive intravitreal injections of recombined tissue plasminogen activator (rtPA), expansile gas and bevacizumab in eyes with acute subretinal haemorrhage (SRH). METHODS: A retrospective, non-randomized consecutive case series included 19 eyes in 19 patients with SRH related to exudative age-related macular degeneration (AMD). The initial size of the subfoveal SRH was 1-3 disc diameters. Each patient received a triple procedure using 0.05 ml rtPA (50 microg), 0.3 ml of sulphur hexafluoride (SF6) gas and 0.05 ml bevacizumab (1.25 mg). Lesion size, location of the SRH and early treatment in diabetic retinopathy study (ETDRS) visual acuity were evaluated pretreatment as well as 1 and 3 months after the procedure. RESULTS: At the initial presentation, the patients' mean age was 77 years (range 63-88 years) and the mean duration of symptoms was 9.3 days (range 4-12 days). The mean visual acuity pretreatment (20/133) improved significantly to 20/86 at 1 month and to 20/74 at 3 months. The mean ETDRS visual acuity improved from baseline by 2.1 lines at 1 month (Wilcoxon ranks test; P < 0.005) and 3.7 lines at 3 months after treatment (Wilcoxon ranks test; P < 0.005). None of our patients had reading visual acuity prior to treatment, with visual acuity below 0.3. One month after the triple procedure, 25% of our patients had reading visual acuity (> or = 0.4); at 3 months, the figure was 35%. A successful inferior displacement of the SRH was achieved in 17/19 eyes. Eyes with elevated intraocular pressure were treated immediately by a corneal paracentesis. CONCLUSION: The intravitreal application of rtPA, gas and bevacizumab appears to be beneficial and well tolerated in the treatment of SRH in the short term. The triple approach seems a logical alternative to the current combined dual approach in limiting the progression of the underlying disease and achieving better visual outcome. Further randomized evaluations are warranted.

Neubauer AS, Holz FG, Schrader W, Back EI, Kühn T, Hirneiss C, Kampik A. · Augenklinik der Ludwig-Maximilians-Universität, München. · Klin Monatsbl Augenheilkd. · Pubmed #17846963 No free full text.

Abstract: PURPOSE: Ranibizumab (Lucentis) stabilizes or improves visual acuity in a high percentage of patients with age-related macular degeneration (AMD). As this therapy is associated with significant costs, the aim of this study was to provide a cost-utility analysis, which considers both costs and utility of a therapy with ranibizumab in an economic model. METHODS: The incremental utility for the patient was modelled based on visual acuity data of the MARINA and ANCHOR study. The utility data used assume that the better seeing eye is affected. The study groups used for comparison consisted of patients who only received best supportive care, e. g., low-vision aids. The baseline scenario of the model assumes 6 treatments per year over a 2 year time period - based on the assessment of an expert panel. Treatment costs were based on German pharmacy prices and recommendations for reimbursement of the intravitreal injections. In a univariate sensitivity analysis all important parameters were varied to assess the stability of the results. RESULTS: The baseline scenario yields for predominantly classic lesions 16,882 euro/QALY (quality adjusted life year), for minimally classic CNV 24,766 euro/QALY and for occult CNV 26,170 euro/QALY. If a distribution of the CNV types with 18 - 25 - 57 % is assumed, the mean cost of therapy with ranibizumab amounts to 24,147 euro/QALY. Sensitivity analysis showed that all reasonable variations yielded results which are considered cost-effective (<or= 50.000 US $/QALY). This is especially true for high and low patient age, for groups with low (0.05 - 0.1) and high ( > 0.4) visual acuity, for a variation of costs per treatment of +/- 20 %, and a prolonged treatment duration of 3 years. CONCLUSIONS: In the investigated szenario a therapy of neovascular AMD with ranibizumab is cost-effective for all angiographic subtypes as well as in the sensitivity analysis.

Ladewig MS, Karl SE, Hamelmann V, Helb HM, Scholl HP, Holz FG, Eter N. · Department of Ophthalmology, University of Bonn, Ernst-Abbe-Strasse 2, 53127, Bonn, Germany. · Graefes Arch Clin Exp Ophthalmol. · Pubmed #17701197 No free full text.

Abstract: BACKGROUND: Our aim was to evaluate the short-term safety and efficacy of combined photodynamic therapy (PDT) with verteporfin and intravitreal bevacizumab in neovascular age-related macular degeneration (AMD). METHODS: A prospective non-randomized interventional case series of 30 eyes of 30 patients with choroidal neovascularization (CNV) caused by AMD was studied. All patients were treated with PDT followed by an intravitreal injection of bevacizumab (1.5 mg) on the same day. Ophthalmic evaluations included determination of best-corrected visual acuity by using ETDRS charts. CNV lesion characteristics were determined by fluorescein angiography, and retinal morphology by optical coherence tomography. Review examinations were performed 1, 4, and 12 weeks following treatment. RESULTS: The median ETDRS letter scores increased by 3 letters after 4 weeks and 4.3 letters after 12 weeks. Median central retinal thickness decreased from the baseline by 145 microm (week 1), 205 microm (week 4), and 171 microm (week 12), respectively (P < 0.0001, for all comparisons). One patient experienced a transient moderate vision loss after 4 weeks post treatment. Leakage on fluorescein angiography was resolved in all patients at week 12. No significant ocular or systemic side-effects were observed. CONCLUSIONS: Short-term results suggest that a single PDT in combination with intravitreal bevacizumab is safe and associated with stabilization of visual acuity and decrease of intraretinal and subretinal fluid accumulation in the macula. Further evaluation of this treatment strategy for neovascular AMD appears warranted.

Dreyhaupt J, Dolar-Szczasny J, Bindewald A, Holz FG, Mansmann U. · Institute of Medical Biometry and Informatics, University of Heidelberg, INF 305, 69120 Heidelberg, Germany. · Methods Inf Med. · Pubmed #17694237 No free full text.

Abstract: OBJECTIVES: Identifying factors influencing the growth of geographic atrophy (GA) in patients with age-related macular degeneration (AMD). METHODS: Data on the natural course and suspected modifying factors were collected as part of the multicenter, longitudinal, observational FAM-study in 178 eyes of 114 patients with atrophic AMD. The endpoint of interest - the size of GA - was measured in fundus autofluorescence images. The influence of different putative risk factors on progression of GA is investigated with a forward selection procedure based on the likelihood ratio test. In order to interpret non-significant results of the forward selection procedure, the power of the tests used was quantified by a parametric post-hoc bootstrap approach. RESULTS: A mean increase in GA of 1.75 mm(2) per year was estimated for the given population (95% CI: [1.46; 2.02]). Patient and eye-specific random effects could be assessed. Neither patient-specific risk factors nor ocular-specific risk factors show any significant influence on GA growth. The post-hoc bootstrap procedure shows that only very strong effects can be detected on the basis of the given data. For example, the hypercholesteremia which would result in an additional increase of GA by near 4 mm(2) per year can be detected with a power of 80%. CONCLUSIONS: The use of linear mixed effects regression models offers a convenient way to explore sources of variation in the natural course of GA. Data from further follow-up examinations and data about other putative risk factors than those investigated will be needed to further investigate of the GA growth process. The procedure described in this article is easily applicable to other putative risk factors as well as to other fields of application.

Han M, Giese G, Schmitz-Valckenberg S, Bindewald-Wittich A, Holz FG, Yu J, Bille JF, Niemz MH. · University of Heidelberg, Mannheim Biomedical Engineering Laboratories, Faculty of Clinical Medicine, Heidelberg, Germany. · J Biomed Opt. · Pubmed #17477727 No free full text.

Abstract: The intensive metabolism of photoreceptors is delicately maintained by the retinal pigment epithelium (RPE) and the choroid. Dysfunction of either the RPE or choroid may lead to severe damage to the retina. Two-photon excited autofluorescence (TPEF) from endogenous fluorophores in the human retina provides a novel opportunity to reveal age-related structural abnormalities in the retina-choroid complex prior to apparent pathological manifestations of age-related retinal diseases. In the photoreceptor layer, the regularity of the macular photoreceptor mosaic is preserved during aging. In the RPE, enlarged lipofuscin granules demonstrate significantly blue-shifted autofluorescence, which coincides with the depletion of melanin pigments. Prominent fibrillar structures in elderly Bruch's membrane and choriocapillaries represent choroidal structure and permeability alterations. Requiring neither slicing nor labeling, TPEF imaging is an elegant and highly efficient tool to delineate the thick, fragile, and opaque retina-choroid complex, and may provide clues to the trigger events of age-related macular degeneration.

Kaemmerer E, Schutt F, Krohne TU, Holz FG, Kopitz J. · Department of Pathology, University of Heidelberg, Heidelberg, Germany. · Invest Ophthalmol Vis Sci. · Pubmed #17325182 links to  free full text

Abstract: PURPOSE: Lipofuscin accumulation in the RPE is a common downstream pathogenic pathway in various monogenic and complex retinal diseases including age-related macular degeneration (AMD). Lipid peroxidation-induced modification of proteins is thought to play a role in lipofuscinogenesis and may contribute to RPE dysfunction. A prior study demonstrated that a variety of lipofuscin-associated proteins are damaged by aberrant covalent modifications of malondialdehyde (MDA) and 4-hydroxynonenal (HNE). The present study was conducted to test the hypothesis that these damaged proteins are more resistant to proteolytic attack and act as protease inhibitors. METHODS: Isolated photoreceptor outer segments (POS) were radioactively labeled and in vitro modified with MDA and HNE. Pure lysosomal fractions isolated from human RPE were tested for their proteolytic activities toward modified and unmodified POS proteins. In parallel, modified and radiolabeled POS were fed to RPE cell cultures for phagocytosis and their lysosomal degradation as well as intracellular accumulation was compared with unmodified POS. RESULTS: Both experimental approaches revealed that MDA or HNE modifications strikingly increase the resistance of POS proteins to the attack by lysosomal proteases. When cultured RPE cells were fed with modified or unmodified POS the amount of degraded POS proteins was reduced by approximately 60% to 70% for the modified POS compared with those in normal control subjects. Some of the modified proteins remained undegraded in the lysosomal compartment of cultured RPE cells and were still detectable 3 weeks after feeding, whereas unmodified POS were completely degraded within 1 week after feeding. Moreover, modified proteins had the potential to impair degradation of unmodified proteins, indicating their efficacy as proteolytic antagonists. CONCLUSIONS: The results indicate that lipid peroxidation-derived protein modifications are involved in lipofuscinogenesis and may contribute to cell damaging effects of lipofuscin in retinal diseases such as AMD.

Holz FG, Bindewald-Wittich A, Fleckenstein M, Dreyhaupt J, Scholl HP, Schmitz-Valckenberg S, Anonymous00266. · Department of Ophthalmology, University of Bonn, Bonn, Germany. · Am J Ophthalmol. · Pubmed #17239336 No free full text.

Abstract: PURPOSE: To test if fundus autofluorescence (FAF) patterns around geographic atrophy (GA) have an impact on GA progression rates over time in atrophic age-related macular degeneration (AMD). DESIGN: Prospective longitudinal multicenter natural history study. METHODS: Standardized digital FAF images were obtained from 195 eyes of 129 patients with GA using confocal scanning laser ophthalmoscopy (excitation 488 nm, emission >500 nm). Areas of GA were quantified and patterns of abnormal FAF in the junctional zone were classified. Repeated FAF images were obtained over a median follow-up period of 1.80 years (interquartile range [IQR], 1.28 to 3.34). RESULTS: Areas of GA (median, 7.04 mm(2) at baseline; IQR, 3.12 to 10.0) showed a median enlargement of 1.52 mm(2)/year (IQR, 0.81 to 2.33). Progression rates in eyes with the banded (median 1.81 mm(2)/year) and the diffuse FAF pattern (1.77 mm(2)/year) were significantly higher compared to eyes without FAF abnormalities (0.38 mm(2)/year) and focal FAF patterns (0.81 mm(2)/year, P < .0001). Within the group of the diffuse pattern, eyes with a diffuse trickling pattern could be identified that exhibited an even higher spread rate (median 3.02 mm(2)/year) compared to the other diffuse types (1.67 mm(2)/year, P = .001). CONCLUSIONS: The results indicate that distinct phenotypic FAF patterns have an impact on disease progression in eyes with atrophic AMD and may therefore serve as prognostic determinants. The findings underscore the relevance of FAF imaging and the pathogenetic role of excessive retinal pigment epithelium (RPE) lipofuscin (LF) accumulation in GA. Natural history data and identification of high-risk characteristics will be helpful to design interventional studies aiming at slowing the spread of atrophy.

Bartz-Schmidt KU, Holz FG. · Augenklinik, Eberhard-Karls-Universität, Schleichstrasse 12, 72076 Tübingen. · Ophthalmologe. · Pubmed #16763861 No free full text.

This publication has no abstract.

Schmitz-Valckenberg S, Bindewald-Wittich A, Dolar-Szczasny J, Dreyhaupt J, Wolf S, Scholl HP, Holz FG, Anonymous00317. · Department of Ophthalmology, University of Bonn, Bonn, Germany, and First Eye Hospital, University of Lublin, Poland. · Invest Ophthalmol Vis Sci. · Pubmed #16723482 links to  free full text

Abstract: PURPOSE: To test the hypothesis that the extension of areas with increased fundus autofluorescence (FAF) outside atrophic patches correlates with the rate of spread of geographic atrophy (GA) over time in eyes with age-related macular degeneration (AMD). METHODS: The database of the multicenter longitudinal natural history Fundus Autofluorescence in AMD (FAM) Study was reviewed for patients with GA recruited through the end of August 2003, with follow-up examinations within at least 1 year. Only eyes with sufficient image quality and with diffuse patterns of increased FAF surrounding atrophy were chosen. In standardized digital FAF images (excitation, 488 nm; emission, >500 nm), total size and spread of GA was measured. The convex hull (CH) of increased FAF as the minimum polygon encompassing the entire area of increased FAF surrounding the central atrophic patches was quantified at baseline. Statistical analysis was performed with the Spearman's rank correlation coefficient (rho). RESULTS: Thirty-nine eyes of 32 patients were included (median age, 75.0 years; interquartile range [IQR], 67.8-78.9); median follow-up, 1.87 years; IQR, 1.43-3.37). At baseline, the median total size of atrophy was 7.04 mm2 (IQR, 4.20-9.88). The median size of the CH was 21.47 mm2 (IQR, 15.19-28.26). The median rate of GA progression was 1.72 mm2 per year (IQR, 1.10-2.83). The area of increased FAF around the atrophy (difference between the CH and the total GA size at baseline) showed a positive correlation with GA enlargement over time (rho=0.60; P=0.0002). CONCLUSIONS: FAF characteristics that are not identified by fundus photography or fluorescein angiography may serve as a prognostic determinant in advanced atrophic AMD. As the FAF signal originates from lipofuscin (LF) in postmitotic RPE cells and since increased FAF indicates excessive LF accumulation, these findings would underscore the pathophysiological role of RPE-LF in AMD pathogenesis.

Owens SL, Bunce C, Brannon AJ, Xing W, Chisholm IH, Gross M, Guymer RH, Holz FG, Bird AC, Anonymous00290. · Moorfields Eye Hospital, London, United Kingdom, and the Universitätsklinikum Benjamin Franklin, Berlin, Germany. · Am J Ophthalmol. · Pubmed #16458680 No free full text.

Abstract: PURPOSE: The Drusen Laser Study evaluated macular laser to prevent choroidal neovascularization (CNV) and vision loss in high-risk age-related maculopathy (ARM). DESIGN: Prospective, interventional, randomized, controlled clinical trial in five hospital centers. METHODS: Patients in the unilateral group had neovascular ARM and drusen in the study eye. Study eyes were randomized to laser-treated or no-laser groups. For patients in the bilateral drusen group, eyes were randomized to right eye, laser or no laser; and left eye, alternative. Laser treatment comprised 12 argon spots. Outcome was best-corrected visual acuity and CNV signs, which were monitored for 3 years. RESULTS: In the unilateral group, vision loss occurred in 21 (28.8%) of 73 patients in laser vs 13 (19.7%) of 66 no-laser patients (P=.214). Incidence of CNV was 27 (29.7%) of 91 in laser vs 15 (17.65%) of 85 no-laser patients (P=.061). CNV onset was approximately 6 months earlier in laser-treated compared with no-laser patients (P=.05). In the bilateral group, vision loss occurred in six (8.3%) of 72 laser-treated vs 10 (13.9%) of 72 fellow eyes (P=.3877). CNV incidence was 12 (11.6%) of 103 in laser-treated vs seven (6.8%) of 103 fellow eyes (P=.225). There was no difference in onset of CNV. CONCLUSIONS: Results do not support prophylactic laser of the fellow eye of patients with neovascular ARM. Its role in patients with bilateral drusen remains unclear.

Bindewald A, Stuhrmann O, Roth F, Schmitz-Valckenberg S, Helb HM, Wegener A, Eter N, Holz FG. · Department of Ophthalmology, University of Bonn, Ernst-Abbe-Strasse 2, D-53127 Bonn, Germany. · Br J Ophthalmol. · Pubmed #16299141 links to  free full text

Abstract: BACKGROUND: With the advent of digital confocal scanning laser ophthalmoscopy it is possible to detect low levels of fluorescence. Here we used a novel confocal scanning laser ophthalmoscope (cSLO) to determine lower limits of dye required for fluorescein (FL) and indocyanine green (ICG) angiography. METHODS: A cSLO (Heidelberg retina angiograph 2, Heidelberg Engineering, Dossenheim, Germany) with an optically pumped solid state laser (488 nm) for FL and a diode laser (790 nm) for ICG angiography (FL/ICG-A) was used. 62 FL-As were performed in 53 patients and 45 ICG-As were performed in 39 patients with neovascular age related macular degeneration. The volume and overall dye content of bolus injections was gradually tapered (FL: 500 mg, 250 mg, 200 mg, 166 mg, 100 mg; ICG: 25 mg, 20 mg, 15 mg, 10 mg, 5 mg, 2.5 mg), while dye concentrations were kept constant at 100 mg/ml for FL and at 5 mg/ml for ICG. Images were obtained 1, 5, 15, and 30 minutes after dye injection. Image quality was evaluated by two independent readers using standardised criteria. RESULTS: For amounts down to 166 mg for FL and to 5 mg for ICG, sufficient image quality was achieved during all phases following injection. Only late phase images showed less contrast compared to typically used dye amounts, which was irrelevant for interpretation and clinical management. CONCLUSIONS: With the increased sensitivity of this novel cSLO system, amounts of injected dye during FL-A can be reduced to one third for FL and to one fifth for ICG without relevant loss of image quality or information compared to conventionally used dye levels. These amounts can be used for routine angiography and allow relevant savings for units performing FL-A.

Dreyhaupt J, Mansmann U, Pritsch M, Dolar-Szczasny J, Bindewald A, Holz FG. · Department of Medical Biometry and Informatics, University of Heidelberg, Germany. · Ophthalmic Epidemiol. · Pubmed #16283987 No free full text.

Abstract: PURPOSE: To model the natural course of geographic atrophy (GA) in patients with age-related macular degeneration (AMD). METHODS: Data on the natural course of GA were collected in the multi-center, longitudinal, prospective observational FAM study. The size of GA was measured by autofluorescence scanning laser ophthalmoscopy. The natural course of GA is modelled by two different mixed effect models (MEM). Both models are compared with respect to the correctness of the model assumptions, goodness of fit, and predictive behavior. RESULTS: The linear model results in better prediction, the non-linear model is more in agreement with the model assumptions. The non-linear model fits the data for small and large areas of GA better, while the linear model seems to be more adequate for the medial areas. More data will be needed to study the interplay of both models in more detail. CONCLUSIONS: The natural course of GA varies extremely between individuals. However, reliable factors for the explanation of this variability have so far not been established. MEM are useful for describing "inter-individual" as well as "intra-individual" influences without the need for precise knowledge of the influencing factors. Using MEM to evaluate data on the natural history of GA allows one to derive parameter estimates, which could be used to design interventional trials for modes of therapy with a potential to reduce or stop the progression of GA in patients with AMD.

Bindewald A, Bird AC, Dandekar SS, Dolar-Szczasny J, Dreyhaupt J, Fitzke FW, Einbock W, Holz FG, Jorzik JJ, Keilhauer C, Lois N, Mlynski J, Pauleikhoff D, Staurenghi G, Wolf S. · Department of Ophthalmology, University of Bonn, Ernst-Abbe-Strasse 2, 53127 Bonn, Germany. · Invest Ophthalmol Vis Sci. · Pubmed #16123434 links to  free full text

Abstract: PURPOSE: To describe and classify patterns of abnormal fundus autofluorescence (FAF) in eyes with early nonexudative age-related macular disease (AMD). METHODS: FAF images were recorded in eyes with early AMD by confocal scanning laser ophthalmoscopy (cSLO) with excitation at 488 nm (argon or OPSL laser) and emission above 500 or 521 nm (barrier filter). A standardized protocol for image acquisition and generation of mean images after automated alignment was applied, and routine fundus photographs were obtained. FAF images were classified by two independent observers. The kappa statistic was applied to assess intra- and interobserver variability. RESULTS: Alterations in FAF were classified into eight phenotypic patterns including normal, minimal change, focal increased, patchy, linear, lacelike, reticular, and speckled. Areas with abnormal increased or decreased FAF signals may or may not have corresponded to funduscopically visible alterations. For intraobserver variability, kappa of observer I was 0.80 (95% confidence interval [CI]0.71-0.89) and of observer II, 0.74. (95% CI, 0.64-0.84). For interobserver variability, kappa was 0.77 (95% CI, 0.67-0.87). CONCLUSIONS: Various phenotypic patterns of abnormal FAF can be identified with cSLO imaging. Distinct patterns may reflect heterogeneity at a cellular and molecular level in contrast to a nonspecific aging process. The results indicate that the classification system yields a relatively high degree of intra- and interobserver agreement. It may be applicable for determination of novel prognostic determinants in longitudinal natural history studies, for identification of genetic risk factors, and for monitoring of future therapeutic interventions to slow the progression of early AMD.

Dwinger MC, Pieper-Bodeewes I, Eter N, Holz FG. · Universitäts-Augenklinik Bonn. · Klin Monatsbl Augenheilkd. · Pubmed #16118744 No free full text.

Abstract: BACKGROUND: Intravitreal triamcinolone injection (IVT) has become a treatment option for macular edema of heterogeneous etiology and neovascular retinal diseases including AMD. Besides the risk for a steroid-induced secondary open-angle glaucoma, the acute rise in intravitreal volume induces IOP elevations immediately after injection. To decrease the intravitreal volume a paracentesis is advocated by many surgeons. The aim of this study was to determine variations in IOP at different time points immediately after IVT in order to assess the necessity for routine paracentesis. METHODS: The IOP was recorded by Goldmann applanation tonometry preoperatively, 10 minutes, 1, 3 and 24 hours after intravitreal injection of 0.1 mL (4 mg) triamcinolone. A consecutive series of 32 eyes of 32 patients with diabetic macular edema, diffuse edema after central vein occlusion or occult subfoveal choroidal neovascularization due to age-related macular degeneration was included. Statistical analysis was performed with ANOVA test and Bonferroni correction. RESULTS: Compared to baseline (15.24 +/- 0.52 mm Hg) IOP was significantly elevated 10 min postoperatively (22.28 +/- 1.4 mmHg; p < 0.05). One hour after injection IOP decreased to 15.58 +/- 0.69 mmHg (p < 0.05). Three and 24 h after injection mean IOP was not significantly different from preoperative baseline levels. Immediately after IVT light perception was tested and retinal perfusion was evaluated by indirect ophthalmoscopy. In none of the patients was a paracentesis necessary. CONCLUSION: Intravitreal injection of 0.1 mL triamcinolone led to a moderate transient rise in IOP. Based on these results, a routinely performed paracentesis immediately before or after IVT is not required. As paracentesis bears an additional risk including endophthalmitis it should only be considered if functional testing following injection indicates a relevant impairment of retinal perfusion.

Bindewald A, Schmitz-Valckenberg S, Jorzik JJ, Dolar-Szczasny J, Sieber H, Keilhauer C, Weinberger AW, Dithmar S, Pauleikhoff D, Mansmann U, Wolf S, Holz FG. · Department of Ophthalmology, University of Bonn, Ernst-Abbe-Strasse 2, D-53127 Bonn, Germany. · Br J Ophthalmol. · Pubmed #15965170 links to  free full text

Abstract: AIM: To describe and classify patterns of abnormal fundus autofluorescence (FAF) in the junctional zone of geographic atrophy (GA) in patients with age related macular degeneration. METHODS: Digital FAF images were recorded in 164 eyes of 107 patients using a confocal scanning laser ophthalmoscope (cSLO; excitation 488 nm, detection above 500 nm) as part of a prospective multicentre natural history study (FAM Study). FAF images were obtained in accordance with a standardised protocol for digital image acquisition and generation of mean images after automated alignment. RESULTS: Image quality was sufficient for classification of FAF patterns in 149 eyes (90.9%) with lens opacities being the most common reason for insufficient image quality. Abnormal FAF outside GA in 149 eyes was classified into four patterns: focal (12.1%), banded (12.8%), patchy (2.0%), and diffuse (57.0%), whereby 12.1% had normal background FAF in the junctional zone. In 4% there was no predominant pattern. The diffuse pattern was subdivided into four groups including reticular (4.7%), branching (27.5%), fine granular (18.1%), and fine granular with peripheral punctate spots (6.7%). CONCLUSIONS: Different phenotypic patterns of abnormal FAF in the junctional zone of GA can be identified with cSLO FAF imaging. These distinct patterns may reflect heterogeneity at a cellular and molecular level in contrast with a non-specific ageing process. A refined phenotypic classification may be helpful to identify prognostic determinants for the spread of atrophy and visual loss, for identification of genetic risk factors as well as for the design of future interventional trials.