Adult vitelliform macular degeneration: a clinicopathological study

Prevalence of Subretinal Drusenoid Deposits in Older Persons with and without Age-Related Macular Degeneration, by Multimodal Imaging

PURPOSE

To assess the prevalence of subretinal drusenoid deposits (SDD) in older adults with healthy maculas and early and intermediate age-related macular degeneration (AMD) using multimodal imaging.

DESIGN

Cross-sectional study.

PARTICIPANTS

A total of 651 subjects aged ≥60 years enrolled in the Alabama Study of Early Age-Related Macular Degeneration from primary care ophthalmology clinics.

METHODS

Subjects were imaged using spectral domain optical coherence tomography (SD OCT) of the macula and optic nerve head (ONH), infrared reflectance, fundus autofluorescence, and color fundus photographs (CFP). Eyes were assessed for AMD presence and severity using the Age-Related Eye Disease Study (AREDS) 9-step scale. Criteria for SDD presence were identification on ≥1 en face modality plus SD OCT or on ≥2 en face modalities if absent on SD OCT. Subretinal drusenoid deposits were considered present at the person level if present in 1 or both eyes.

MAIN OUTCOME MEASURES

Prevalence of SDD in participants with and without AMD.

RESULTS

Overall prevalence of SDD was 32% (197/611), with 62% (122/197) affected in both eyes. Persons with SDD were older than those without SDD (70.6 vs. 68.7 years, P = 0.0002). Prevalence of SDD was 23% in subjects without AMD and 52% in subjects with AMD (P < 0.0001). Among those with early and intermediate AMD, SDD prevalence was 49% and 79%, respectively. After age adjustment, those with SDD were 3.4 times more likely to have AMD than those without SDD (95% confidence interval, 2.3-4.9). By using CFP only for SDD detection per the AREDS protocol, prevalence of SDD was 2% (12/610). Of persons with SDD detected by SD OCT and confirmed by at least 1 en face modality, 47% (89/190) were detected exclusively on the ONH SD OCT volume.

CONCLUSIONS

Subretinal drusenoid deposits are present in approximately one quarter of older adults with healthy maculae and in more than half of persons with early to intermediate AMD, even by stringent criteria. The prevalence of SDD is strongly associated with AMD presence and severity and increases with age, and its retinal topography including peripapillary involvement resembles that of rod photoreceptors. Consensus on SDD detection methods is recommended to advance our knowledge of this lesion and its clinical and biologic significance.

Characterising the phenotype and progression of sporadic adult-onset foveomacular vitelliform dystrophy

BACKGROUND/AIMS

Adult-onset foveomacular vitelliform dystrophy (AFVD) is a relatively common macular degeneration which might lead to substantial visual loss. Our purpose was to describe the natural course of genetically evaluated patients with sporadic AFVD.

METHODS

A retrospective, consecutive, cohort study included 95 eyes of 51 patients. Mutations in genes previously associated with AFVD (PRPH2, BEST1, IMPG-1 and IMPG-2) were evaluated. Demographics, clinical characteristics, and spectral domain optical coherence tomography features were analysed. Main outcome measures were changes in the best corrected visual acuity (BCVA) and lesion morphology during the follow-up.

RESULTS

The mean age (±SD) at diagnosis was 73.8±10.7 years. Mean (±SD) follow-up period was 30.4±16.3 months (range 0-44 months; median 25 months). All patients were genotyped negative for the evaluated mutations. Fifty-three of the eyes were followed for at least 36 months. At baseline these eyes had a mean BCVA (±SD) of 0.27±0.35 LogMAR, and at 36-months BCVA decreased to 0.38±0.35 (p=0.02). At baseline, 23 of these 53 eyes (43.4%) had the vitelliform stage, while only 10 eyes (18.9%) remained at this stage at 36 months (p=0.01). Ellipsoid zone alterations progressed during the follow-up (n=53 eyes) and showed correlation with BCVA reduction (Pearson's correlation coefficient=0.7, p=0.03).

CONCLUSIONS

Sporadic AFVD is a slowly progressing macular degeneration of older people. It is associated with visual decline at the rate of approximately one ETDRS line during 3 years. Patients with sporadic AFVD are usually negative for the known mutations previously associated with this phenotype, and present at an age that is higher than described for monogenic AFVD.

Enhanced depth imaging optical coherence tomography in adult-onset foveomacular vitelliform dystrophy

PURPOSE

To compare mean choroidal thickness in patients with adult-onset foveomacular vitelliform dystrophy (AOFVD) and healthy subjects, to analyze patients with AOFVD in order to evaluate choroidal thickness disease-related changes, also in relation to the different stages of AOFVD disease and to the retinal pigment epithelium (RPE) features, and to correlate mean choroidal thickness with age in both groups.

METHODS

In this prospective observational cross-sectional study, a total of 63 eyes of 51 consecutive subjects were examined, consisting of a control group (n = 28 eyes) and the AOFVD group (n = 35 eyes). A complete ophthalmologic examination, fundus autofluorescence, and spectral-domain optical coherence tomography were performed in all patients.

RESULTS

Mean subfoveal choroidal thickness was 214.78 ± 62.35 µm in healthy subjects and 222.31 ± 73.29 µm in the AOFVD group (p = 0.33). In the vitelliruptive group, the mean choroidal thickness was significantly thicker than in the control group at each choroidal location. Mean choroidal thickness was significantly increased in the pseudohypopyon stage when compared to the vitelliform one (+66.34 µm, p = 0.02). Eyes with subretinal fluid (SRF) showed significantly thicker choroid when compared with those without SRF. No significant correlations were found between age and choroidal thickness in the study group.

CONCLUSIONS

The study of the choroid in patients with AOFVD suggested a possible role in the pathologic changes during the different stages of disease, and could help us to evaluate progression of the disease. Greater choroidal thickness associated with SRF and RPE bumps are signs of RPE alterations and could be related to evolution of the AOFVD lesion to a different stage.

Near-infrared fundus autofluorescence in subclinical best vitelliform macular dystrophy

PURPOSE

To describe fundus autofluorescence (FAF) on short-wavelength FAF and near-infrared FAF in the subclinical form of Best vitelliform macular dystrophy.

DESIGN

Cross-sectional prospective study.

METHODS

Patients affected by the subclinical form of Best vitelliform macular dystrophy (positive testing for BEST1 gene mutation, fully preserved best-corrected visual acuity, normal fundus appearance) were recruited. Each patient underwent a complete ophthalmologic examination, including electro-oculogram (EOG), short-wavelength FAF, near-infrared FAF, spectral-domain OCT (SD OCT), and microperimetry. Main outcome measure was the identification of abnormal FAF patterns.

RESULTS

Forty-six patients showing mutations in the BEST1 gene were examined. Forty patients presented a bilateral Best vitelliform macular dystrophy, 2 patients showed a unilateral Best vitelliform macular dystrophy, and 4 patients had a bilateral subclinical form. Patients with the unilateral form (2 eyes) and patients with the subclinical form (8 eyes) were analyzed. Three BEST1 sequence variants were identified: c.73C>T (p.Arg25Trp), c.28G>A (p.Ala10Thr), and c.652C>G (p.Arg218Gly). Short-wavelength FAF was normal in all eyes. Near-infrared FAF detected a pattern consisting of a central hypo-autofluorescence surrounded by a round area of hyper-autofluorescence. A bilateral reduced EOG response was detected in 1 patient. SD OCT revealed a thicker, well-defined, and more reflective interdigitation zone in 2 patients (4 eyes, 40%). Microperimetry of the central 10 degrees revealed a slight, diffuse reduction of retinal sensitivity. Mean retinal sensitivity within the central 2 and 4 degrees was lower and matched the hypo-autofluorescent area detected on near-infrared FAF. Additional relative scotomata were detected within the 10-degree area. No change in clinical, functional, or FAF pattern was found over the follow-up.

CONCLUSIONS

Subclinical Best vitelliform macular dystrophy is characterized by the absence of biomicroscopic fundus abnormality and fully preserved visual acuity, but shows an abnormal near-infrared FAF pattern, with central hypo-autofluorescence.

Subretinal drusenoid deposits in non-neovascular age-related macular degeneration: morphology, prevalence, topography, and biogenesis model

PURPOSE

To characterize the morphology, prevalence, and topography of subretinal drusenoid deposits, a candidate histological correlate of reticular pseudodrusen, with reference to basal linear deposit (BlinD), a specific lesion of age-related macular degeneration, and to propose a biogenesis model for both lesion.

METHODS

Donor eyes with median death-to-preservation of 2:40 hours were postfixed in osmium tannic acid paraphenylenediamine and prepared for macula-wide high-resolution digital sections. Annotated thicknesses of 21 chorioretinal layers were determined at standard locations in sections through the fovea and the superior perifovea.

RESULTS

In 22 eyes of 20 white donors (83.1 ± 7.7 years), SDD appeared as isolated or confluent drusenoid dollops punctuated by tufts of retinal pigment epithelium apical processes and associated with photoreceptor perturbation. Subretinal drusenoid deposits and BlinD were detected in 85 and 90% of non-neovascular age-related macular degeneration donors, respectively. Subretinal drusenoid deposit was thick (median, 9.4 μm) and more abundant in the perifovea than in the fovea (P < 0.0001). BlinD was thin (median, 2.1 μm) and more abundant in the fovea than in the perifovea (P < 0.0001).

CONCLUSION

Subretinal drusenoid deposits and BlinD prevalence in age-related macular degeneration eyes are high. Subretinal drusenoid deposits organized morphology, topography, and impact on surrounding photoreceptors imply specific processes of biogenesis. Contrasting topographies of subretinal drusenoid deposits and BlinD suggest relationships with differentiable aspects of rod and cone physiology, respectively. A 2-lesion 2-compartment biogenesis model incorporating outer retinal lipid homeostasis is presented.

Optical coherence tomography for multifocal vitelliform macular dystrophy

PURPOSE

To describe the optical coherence tomography (OCT) features of multifocal vitelliform macular dystrophy (VMD).

METHODS

Five patients (10 eyes) with multifocal VMD were examined by slit lamp biomicroscopy, fundus photography, and OCT.

RESULTS

Serous retinal detachment was present in the macular area in all eyes. A hyperreflective inner/outer segment interface was observed in the macula in nine of them. High reflectivity was homogeneous in six eyes of three patients with no prominent macular lesion. Retinoschisis-like changes could be clearly seen in four eyes evaluated by high-resolution OCT. A hyporeflectivity corresponded to the inner nuclear layer in two eyes. In four eyes with prominent macular lesions, a hyperreflective area between the hyporeflective outer nuclear layer and the hyperreflective retinal pigment epithelium layer was detectable.

CONCLUSIONS

Although the fundus appearance of multifocal VMD is quite variable, OCT features of the disease are relatively uniform. Optical coherence tomography could help the pathological interpretation and facilitate the diagnosis of VMD.

Ultrastructural and clinical evidence of subretinal debris accumulation in type 2 macular telangiectasia

Aims

To describe subretinal debris found on ultrastructural examination in an eye with macular telangiectasia (MacTel) type 2 and on optical coherence tomography (OCT) in a subset of patients with MacTel type 2.

Methods

Blocks from the mid-periphery and temporal perifovea of an eye with clinically documented MacTel type 2 were examined with electron microscopy (EM). Cases came from the Sydney centre of the MacTel project and the practices of the authors.

Results

On EM examination, subretinal debris was found in the perifovea with accumulation of degenerate photoreceptor elements in the subretinal space. Despite the substantial subretinal debris, there was minimal retinal pigment epithelial (RPE) reaction. Focal defects were seen in the inner limiting membrane in the perifovea. Of the 65 Sydney MacTel project participants, three (5%) had prominent yellow material at the fovea. OCT revealed smooth mounds between the RPE and the ellipsoid region. The material was hyperautofluorescent.

Conclusions

This study suggests that subretinal accumulation of photoreceptor debris may be a feature of MacTel type 2. Ultrastructural and OCT evidence of disease beyond the vasculature, involving photoreceptors and Muller cells, is presented.

Giant macular hole with Best's disease in a young boy

An eight-year-old boy presented with decreased near and distance vision in both eyes. The right ocular fundus showed a giant macular hole surrounded by a vitelliform ring. Spectral domain optical coherence tomography (SD-OCT) revealed a full-thickness macular hole with cystic spaces at the edges. The left fundus had an egg-yolk like appearance of 1.5-disc diameter at the macular region. SD-OCT showed an optically empty space between retinal pigment epithelium and the neurosensory retina. Fundus autofluorescence confirmed the presence of lipofuscin in both eyes. The Arden ratio was 1.38 for the right eye and 1.61 for the left. There was no surgical intervention because of the poor prognosis due to large size of the hole. Environmental modification and contrast-enhancing measures were explained to the patient and his parents.

Natural course of adult-onset foveomacular vitelliform dystrophy: a spectral-domain optical coherence tomography analysis

PURPOSE

To describe the natural course of adult-onset foveomacular vitelliform dystrophy using spectral-domain optical coherence tomography (SD-OCT).

DESIGN

Retrospective study.

METHODS

We reviewed the charts of all consecutive patients with adult-onset foveomacular vitelliform dystrophy who underwent SD-OCT at baseline and at least 12 months later (last visit). Main outcome measures were changes of clinical and SD-OCT features over time.

RESULTS

Forty-six eyes (31 patients, 15 male and 16 female; mean age 74.6 ± 8.2 years) were included. Follow-up was 16.2 ± 6 (range, 12-30) months. Visual acuity (VA) reduced from 0.32 ± 0.22 logMAR at baseline to 0.39 ± 0.28 logMAR at last visit (P=.03). The stage of the disease was vitelliform in 28 eyes (60.8%), pseudohypopyon in 7 eyes (15.2%), vitelliruptive in 11 eyes (23.9%) at baseline; vitelliform in 23 eyes (50%), pseudohypopyon in 5 eyes (10.9%), vitelliruptive in 13 eyes (28.2%), and atrophic in 5 eyes (10.9%) at last visit. Stabilization of the disease stage, inner segment/outer segment (IS/OS) interface status, and lesion reflectivity on SD-OCT determined no VA changes (P>.05), while their worsening determined a reduction of VA (P=.03). In eyes that presented a progression of the disease stage, mean central macular thickness, maximal thickness of the lesion, and maximal width of the lesion showed a significant change (from 404.1 ± 107.6 μm to 246.1 ± 74.0 μm, P = .004; from 277.0 ± 80.8 μm to 105.3 ± 92.3 μm, P=.001; from 2324.2 ± 1250.3 μm to 1751.0 ± 858.3 μm, P = .04, respectively).

CONCLUSIONS

In adult-onset foveomacular vitelliform dystrophy, progression of the lesion stage (partial/complete resorption of the material) is generally accompanied by IS/OS interface disruption/loss and visual impairment.

Multimodal fundus imaging of pseudoxanthoma elasticum

PURPOSE

To investigate spectral domain optical coherence tomography and autofluorescence findings in eyes with pseudoxanthoma elasticum.

METHODS

A retrospective analysis of visual acuity, spectral domain optical coherence tomography, and autofluorescence findings of consecutive patients with pseudoxanthoma elasticum was performed. The spectral domain optical coherence tomography was evaluated for retinal architecture, subretinal accumulations, and photoreceptor layer thickness. Autofluorescence and near-infrared reflectance images were reviewed for correlative findings.

RESULTS

There were 21 patients (42 eyes) with pseudoxanthoma elasticum with a mean age of 56.1 ± 12.4 years. Subretinal fluid was found in 14 eyes, 7 of which had no signs of choroidal neovascularization. In six of the seven eyes with a history of choroidal neovascularization controlled with antivascular endothelial growth factor injections, there were areas of subretinal fluid that were not contiguous with the choroidal neovascularization and did not seem responsive to antivascular endothelial growth factor injections. Two types of formed material were observed in the subretinal space and outer retina. The first was hypoautofluorescent deposits above the retinal pigment epithelium resembling subretinal drusenoid deposits (reticular pseudodrusen). The second was yellow to brown hyperautofluorescent aggregates in the subretinal space and outer retina similar to those seen in pattern dystrophies and was found in 19 eyes. There was an apparent association between the presence of subretinal fluid and pattern dystrophy-like findings.

CONCLUSION

Subretinal fluid in patients with pseudoxanthoma elasticum is not always indicative of active leakage from underlying choroidal neovascularization and can be resistant to antivascular endothelial growth factor injections. This fluid is associated with pattern dystrophy-like findings and may indicate abnormal retinal pigment epithelial function.

mTOR-mediated dedifferentiation of the retinal pigment epithelium initiates photoreceptor degeneration in mice

Retinal pigment epithelial (RPE) cell dysfunction plays a central role in various retinal degenerative diseases, but knowledge is limited regarding the pathways responsible for adult RPE stress responses in vivo. RPE mitochondrial dysfunction has been implicated in the pathogenesis of several forms of retinal degeneration. Here we have shown that postnatal ablation of RPE mitochondrial oxidative phosphorylation in mice triggers gradual epithelium dedifferentiation, typified by reduction of RPE-characteristic proteins and cellular hypertrophy. The electrical response of the retina to light decreased and photoreceptors eventually degenerated. Abnormal RPE cell behavior was associated with increased glycolysis and activation of, and dependence upon, the hepatocyte growth factor/met proto-oncogene pathway. RPE dedifferentiation and hypertrophy arose through stimulation of the AKT/mammalian target of rapamycin (AKT/mTOR) pathway. Administration of an oxidant to wild-type mice also caused RPE dedifferentiation and mTOR activation. Importantly, treatment with the mTOR inhibitor rapamycin blunted key aspects of dedifferentiation and preserved photoreceptor function for both insults. These results reveal an in vivo response of the mature RPE to diverse stressors that prolongs RPE cell survival at the expense of epithelial attributes and photoreceptor function. Our findings provide a rationale for mTOR pathway inhibition as a therapeutic strategy for retinal degenerative diseases involving RPE stress.

In vivo visualization of photoreceptor layer and lipofuscin accumulation in stargardt's disease and fundus flavimaculatus by high resolution spectral-domain optical coherence tomography

INTRODUCTION

To assess photoreceptor (PR) layer morphology in patients with Stargardt's disease (STGD) and fundus flavimaculatus (FFM) using high resolution spectral domain optical coherence tomography (HD-OCT; OCT 4000 Cirrus, Humphrey-Zeiss, San Leandro, CA).

METHODS

This was a prospective observational case series. Sixteen consecutive patients with STGD and FFM underwent a complete ophthalmologic examination. Optical coherence tomography examination was performed with HD-OCT, a high-speed (27,000 axial scans per second) OCT system using spectral/Fourier domain detection, with an axial image resolution of 5 mum.

RESULTS

A total of 31 eyes were included in the study. Transverse loss of the PR layer in the foveal region was shown by HD-OCT. Twenty eyes with clinically evident central atrophy had a disruption of either the Verhoeff's membrane (VM) or the layer corresponding to the interface of inner segment (IS) and outer segment (OS) of PR in the foveal region. Among these eyes, 12/20 eyes had a loss of the PR layer (loss of both VM and IS-OS interface) in the foveal region. Eleven eyes (11/31) without clinically evident central atrophy had an intact interface of IS and OS of PR centrally. Moreover, we observed hyperreflective deposits: type 1 lesions located within the retinal pigment epithelium (RPE) layer and at the level of the outer segments of PR, and type 2 lesions located at the level of the outer nuclear layer and clearly separated from the RPE layer. Type 1 lesions alone were associated with absence of loss of the PR layer in the foveal region in all eyes; type 2 lesions were always associated with presence of type 1 lesions, and often (8/12 eyes) associated with loss of the PR layer within the foveal region. Mean best-corrected visual acuity (BCVA) was significantly correlated with loss of the PR layer in the foveal region (P < 0.001), as well as to presence of type 2 flecks (P = 0.03).

CONCLUSION

Type 2 deposits in STGD/FFM patients seem to represent a marker of the possible evolution towards foveal atrophy.

High-definition optical coherence tomography features in vitelliform macular dystrophy

PURPOSE

To correlate high-definition optical coherence tomography (HD OCT) and fundus examination findings at different phases of vitelliform macular dystrophy and to determine the anatomic location of vitelliform material.

DESIGN

Prospective, noncomparative, observational case series.

METHODS

A complete ophthalmologic examination, including fundus biomicroscopy and HD OCT, was performed in 11 consecutive patients with a diagnosis of vitelliform macular dystrophy.

RESULTS

Using HD OCT, we were able to demonstrate for the first time the presence of previtelliform lesions, characterized by a thicker layer between the retinal pigment epithelium (RPE) and the inner segment and outer segment (IS/OS) interface. At this stage, a normal-appearing RPE and IS/OS interface were found in two of four eyes. In all progressive stages from the vitelliform to the vitelliruptive, the vitelliform material was visualized by HD OCT as an highly reflective lesion located between the hyporeflective outer nuclear layer and the hyperreflective RPE layer, associated or not to an optically empty lesion. At these stages, a disrupted IS/OS interface and an almost normal appearance of all major intraretinal layers was detected. At the vitelliruptive and atrophic stages, on some parts, the HD OCT scan revealed hyperreflective mottling on the RPE layer, probably representing areas of focal RPE hypertrophy. The atrophic stage and the fibrotic stage were characterized by thinning of all the retinal layers and diffuse loss of the IS/OS interface. In our series, mean best-corrected visual acuity impairment showed a statistically significant correlation to the presence of focal disruption or diffuse loss of the IS/OS interface (P = .002), as well as to a more advanced stage of the disease (P = .01). A more advanced stage of the disease showed a strong statistically significant correlation to the presence of diffuse loss of the IS/OS interface (P < .001).

CONCLUSIONS

Based on the HD OCT findings, we hypothesize that early changes in vitelliform macular dystrophy involve the layer between the RPE and the IS/OS interface, first with accumulation of material beneath the sensory retina, and then with disruption and attenuation of IS and OS; late changes seem to affect the RPE, which undergoes hypertrophy, disruption, and attenuation.

Autofluorescence from the outer retina and subretinal space: hypothesis and review

PURPOSE

To review the pathophysiologic principles underlying increased autofluorescence from the outer retina and subretinal space using selected diseases as examples.

METHODS

The ocular imaging information and histopathologic features, when known, were integrated for diseases causing increased autofluorescence from the outer retina and subretinal space. Inferences were taken from this information and used to create a classification scheme.

RESULTS

These diseases are principally those that cause separation of the outer retina from the retinal pigment epithelium, thereby preventing proper phagocytosis of photoreceptor outer segments. The separation can arise from increased exudation into the subretinal space or inadequate removal of fluid from the subretinal space. Lack of normal outer segment processing initially leads to increased accumulation of outer segments on the outer retina and subretinal space. Over time, this material is visible as an increasingly thick coating on the outer retina, is yellow, and is autofluorescent. Over time, atrophy develops with thinning of the deposited material and decreasing autofluorescence. The accumulated material is ultimately capable of inducing damage to the retinal pigment epithelium. Diseases causing accumulation of the material include central serous chorioretinopathy, vitelliform macular dystrophy, acute exudative polymorphous vitelliform maculopathy, choroidal tumors, and vitreomacular traction syndrome.

CONCLUSION

The physical separation of the retinal outer segments from the retinal pigment epithelium hinders proper phagocytosis of the outer segments. Accumulation of the shed but not phagocytized outer segments plays a role in disease manifestations for a number of macular diseases.

Real-time in vivo imaging of retinal cell apoptosis after laser exposure

PURPOSE

To investigate whether the detection of apoptosing retinal cells (DARC) could detect cells undergoing apoptosis in a laser model of retinal damage.

METHODS

Laser lesions were placed, with the use of a frequency-doubled Nd:YAG laser, on the retina in 34 eyes of anesthetized Dark Agouti rats. Lesion size and laser-induced retinal elevation were analyzed using in vivo reflectance imaging. Development of retinal cell apoptosis was assessed using intravitreal fluorescence-labeled annexin 5 in vivo with DARC technology from baseline until 90 minutes after laser application. Histologic analysis of retinal flat mounts and cross-sections was performed.

RESULTS

The lateral and anteroposterior depth extension of the zone of laser damage was significantly larger for higher exposure settings. A strong diffuse signal, concentrated at the outer retina, was seen with DARC for low exposures (<300 ms and <300 mW). In comparison, higher exposures (>300 ms and >300 mW) resulted in detectable hyperfluorescent spots, mainly at the level of the inner retinal layers. Dose-dependent effects on spot density and positive correlation of spot density between lesion size (P < 0.0001) and retinal elevation (P < 0.0001) were demonstrated. Histology confirmed the presence of apoptosing retinal cells in the inner nuclear and the ganglion cell layers.

CONCLUSIONS

This is the first time that DARC has been used to determine apoptotic effects in the inner nuclear layer. The ability to monitor changes spatially and temporally in vivo promises to be a major advance in the real-time assessment of retinal diseases and treatment effects.

Using contrast sensitivity to estimate the cost-effectiveness of verteporfin in patients with predominantly classic age-related macular degeneration

AIMS

To re-evaluate the cost-effectiveness of photodynamic therapy with verteporfin (Visudyne, Novartis AG, Switzerland) in patients with predominantly classic and classic choroidal neovascularization (CNV) owing to age-related macular degeneration (AMD), using new evidence on the impact of contrast sensitivity on health status.

METHOD

A health economic model is used to synthesise the evidence on contrast sensitivity and treatment rates from the TAP Investigation with health state utilities and costs. Impairment of visual function is estimated using a Markov model to predict transitions between states of contrast sensitivity. Each state is associated with costs and a health state utility. Total expected costs and benefits for a cohort of patients over a defined number of cycles are calculated. The expected health state utility for each disease state was estimated using results from a study of 209 patients with AMD in Sheffield. The model includes the costs associated with treatment and monitoring in the verteporfin treatment arm and costs offset by delaying the deterioration of visual function.

RESULTS

Beyond 3 years, the annual costs of the verteporfin arm are estimated to be less than the annual costs of the control arm, owing to the cost associated with higher blindness prevalence in the control arm. Over time, the results show that both the incremental utility and cost decreases. By 10 years, the estimated incremental cost-effectiveness is approximately pound20 996 per Quality-Adjusted Life Years.

CONCLUSION

The results of this study suggest that the verteporfin therapy in the treatment for patients with predominantly classic and classic CNV owing to AMD is encouraging.