Fundus autofluorescence in patients with macular holes imaged with a laser scanning ophthalmoscope

Abstract

Aim-To demonstrate the usefulness of a recently developed technique of imaging fundus autofluorescence and to compare it with the results of fluorescein angiography in the diagnosis and staging of macular holes. Methods-The intensity and distribution of fundus autofluorescence was studied in 51 patients with idiopathic macular holes and pseudoholes using a confocal laser scanning ophthalmoscope (cLSO) and the images were compared with those obtained by fundus fluorescein angiography. (Br J Ophthalmol 1998;82:346-351) The diagnosis of idiopathic full thickness macular holes (FTMH) is usually made by history and by biomicroscopic examination. However, at times it may be diYcult to diVerentiate between a FTMH and a macular pseudohole even using otherwise reliable clinical tests such as the Watzke-Allen slit beam test. Results-Autofluorescence1 In such cases fluorescein angiography is used but this has the disadvantage of being invasive, requiring an intravenous injection of sodium fluorescein which carries a potential risk of adverse reactions. 2Recently a new technique has been developed that allows in vivo imaging of the distribution of fundus autofluorescence using a confocal laser scanning ophthalmoscope (cLSO).3 This provides high spatial resolution imaging of the distribution of fundus autofluorescence which is most likely derived from lipofuscin within the retinal pigment epithelium.3-5 It is generally accepted that lipofuscin represents the product of degradation of photoreceptor outer segments. In a normal fundus, the distribution of fundus autofluorescence is diVuse, with decreased intensity at the fovea, at the optic nerve head, and under the retinal blood vessels which appear dark.3 4 As this technique images the intrinsic fluorescence of the fundus derived from the retinal pigment epithelium, 3-5 it should be possible to demonstrate a macular defect such as the FTMH similar to that seen on fluorescein angiography.In this study we obtained images of the intrinsic autofluorescence of the fundus with a cLSO in patients with macular holes and pseudoholes and compared the images with those obtained by fluorescein angiography. Material and methodsThe technique of imaging fundus autofluorescence has been described previously.3 4 Briefly the cLSO used in this study was a prototype (SM 30-4024) donated by Zeiss (Zeiss, Oberkochen, Germany). The argon laser (wavelength 488 nm and power of 250 µW) was used for illumination, and to record autofluorescence a filter with a cut oV at 521 nm was inserted in front of the detector. The cLSO images were recorded at standard video scanning rates on SVHS video tape and digitised at 256 × 256 resolution using a Wide Vision V-10 frame grabber (Wild Vision, Tyne and Wear) with an Acorn Archimedes computer (Acorn Computers, Cambridge).A prospective study was undertaken of patients with unilateral idiopathic FTMH and with macular pseudoholes. We deliberately selected only patients with unilateral macular holes in order to compare the autofluorescence images and the...

In vivo imaging of retinal pigment epithelium cells in age related macular degeneration

“…Morgan and colleagues later demonstrated that these methods could be used to achieve single cell resolution of the RPE in the living human eye [17]. Since the RPE is important for maintaining the healthy function of the photoreceptor layer and is implicated in many retinal diseases, such as AMD [7][8][9][10][11], the demonstration that these cells were now accessible to optical imaging in the living human eye was a potentially valuable advance. However, our early attempts to image the RPE in patients with AMD using these methods proved difficult; we were able to obtain images with greater structural detail than commercial systems, but individual cells could not be resolved [18,19].…”

“…These changes may precede and/or accompany RPE cell death and the degeneration of overlying photoreceptors [4,6]. Clinical imaging methods, such as confocal scanning laser ophthalmoscopy (cSLO), are used to examine the FAF pattern as a means of assessing the health of the RPE in AMD and other retinal diseases [7][8][9][10][11]. However, currently available commercial fundus autofluorescence (FAF) imaging systems lack the resolution to identify individual cells, preventing morphometric analysis of the RPE cell mosaic.…”

Quantitative evaluation of experimental choroidal neovascularization by confocal scanning laser ophthalmoscopy: fluorescein angiogram parallels heparan sulfate proteoglycan expression

“…The in vivo autofluorescence of human retinal pigmented epithelium (RPE) provides a noninvasive technique that can be used in the investigation of inherited and age-related retinal diseases (36,37), permitting the assessment of the viability of the RPE/photoreceptor complex by the distribution of the levels of retinal fluorophores (38). The ocular fundi of individuals with degenerative macular diseases such as age-related macular degeneration show a dramatic, agedependent accumulation of retinal fluorophores (38).…”

Fundus Autofluorescence

“…There is a fine ring of hypoAF just surrounding the hole due to the upturned edges of the macular hole which constitutes of tissue containing luteal pigments and also because the increased thickness there impedes the passage of the excitation rays. 18 Following a successful macular hole surgery, the FAF returns to a normal pattern. (Figure 7) …”