Dataset Information

Development of atrophy of the retinal pigment epithelium around disciform scars.

ABSTRACT:

Background/aims

Eyes with burnt out disciform scars secondary to age related macular degeneration (AMD) are regarded as visually stable. The aim of this study is to report the subsequent development of atrophy of the retinal pigment epithelium (RPE) around the scars and discuss the possible basis.

Methods

20 eyes from 18 patients were observed to develop atrophy around choroidal neovascularisation (CNV). A method of measuring expansion of the atrophy over time is described using the Topcon Imagenet 2000 system. An additional 10 clinicopathological examples were reviewed.

Results

Clinically CNV became surrounded initially by a ring of pallor that progressed to an expanding band of atrophy of the RPE. It developed most rapidly in the first 3 years after CNV became quiescent but then continued to expand slowly to more than three times the size of the scar. Histopathological specimens showed large choroidal vessels entering the scars directly and a reduced number of small choroidal vessels beneath and around the scar

Conclusions

Disciform scars may become surrounded by an expanding band of atrophy of the RPE, postulated to result from remodelling of the choroidal circulation. The ongoing enlargement of the resulting scotoma may need to be considered when planning management and assessing treatment outcomes.

SUBMITTER: Sarks J

PROVIDER: S-EPMC1857011 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature

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Publications

Development of atrophy of the retinal pigment epithelium around disciform scars.

Sarks J J Tang K K Killingsworth M M Arnold J J Sarks S S

The British journal of ophthalmology 20060401 4

<h4>Background/aims</h4>Eyes with burnt out disciform scars secondary to age related macular degeneration (AMD) are regarded as visually stable. The aim of this study is to report the subsequent development of atrophy of the retinal pigment epithelium (RPE) around the scars and discuss the possible basis.<h4>Methods</h4>20 eyes from 18 patients were observed to develop atrophy around choroidal neovascularisation (CNV). A method of measuring expansion of the atrophy over time is described using t ...[more]

PMID: 16547324

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Project description:PurposeLipofuscin contained in the retinal pigment epithelium (RPE) is the main source of fundus autofluorescence (FAF), the target of an imaging method useful for estimating the progression of geographic atrophy (GA) in clinical trials. To establish a cellular basis for hyperfluorescent GA border zones, histologic autofluorescence (HAF) was measured at defined stages of RPE pathologic progression.DesignExperimental study.Participants and controlsTen GA donor eyes (mean age ± standard deviation, 87.1 ± 4.0 years) and 3 age-matched control eyes (mean age ± standard deviation, 84.0 ± 7.2 years) without GA.MethodsThe 10-micrometer-thick sections were divided into zones of RPE morphologic features according to an 8-point scale. Any HAF excited by 488 nm light was imaged by laser confocal microscopy. The HAF intensity summed along vertical lines perpendicular to Bruch's membrane at 0.2-?m intervals served as a surrogate for FAF. Intensity profiles in 151 zones were normalized to grade 0 at a standard reference location in each eye. Cross-sectional area, mean, and sum autofluorescence for individual RPE cells were measured (cellular autofluorescence [CAF]).Main outcome measuresStatistically significant differences in intensity and localization of HAF and CAF at defined stages of RPE morphologic progression for GA and control eyes.ResultsThe RPE morphologic features were most abnormal (cell rounding, sloughing, and layering; grade 2) and HAF intensity profiles were highest and most variable immediately adjacent to atrophic areas. Peaks in HAF intensity frequently were associated with vertically superimposed cells. The HAF value that optimally separated reactive RPE was 0.66 standard deviations more than the mean for uninvolved RPE and was associated with a sensitivity of 75.8% and a specificity of 76.3%. When variable cell area was accounted for, neither mean nor sum CAF differed significantly among the RPE pathologic grades.ConclusionsAreas with advanced RPE alterations are most likely to exhibit clinically recognizable patterns of elevated FAF around GA, but may not predict cells about to die, because of vertically superimposed cells and cellular fragments. These data do not support a role for lipofuscin-related cell death and call into question the rationale of treatments targeting lipofuscin.

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Dataset Information

Development of atrophy of the retinal pigment epithelium around disciform scars.

Background/aims

Methods

Results

Conclusions

Publications

Development of atrophy of the retinal pigment epithelium around disciform scars.

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