Ophthalmoscopy
When studying the fundus with indirect, direct, or slit-lamp ophthalmoscopy, the different elements should be studied in the following order:
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Ophthalmoscopy
Contents 24.1
Generalities.................................................... 341
24.2
Ophthalmoscopes and Lenses for Studying the Fundus Oculi .................... 342
24.3
Alterations of the Optic Nerve Head........... 342
24.4
Evolution of the Optic Disk from Normal to Glaucomatous Cupping ............. 342
References ................................................................. 351
24.1
Generalities
When studying the fundus with indirect, direct, or slit-lamp ophthalmoscopy, the different elements should be studied in the following order: Arteries: First, we study their size: normal, thickened, thinned; and then their caliber— regular, irregular, with functional narrowing (spasms), with organic narrowing (arteriosclerosis), rosary arteries, etc. Veins: Normal, thickened, congestive, and throbbing vein in the optic disk. Artery-vein ration: Normal—vein 3 artery 2. This ratio is modified at the expense of the veins or at the expense of the arteries. When the arteries are thin, the ratio is altered, for example, 2–1, 3–1, 4–1, and 5–1. When it is at the expense of the veins, it is altered in the same way. This is usually a case of congested veins. Artery-vein crossings: They have value if they are observed from at least three disk diameters toward the periphery. They will be normal, marked, or very marked. It is generally the product of atherosclerosis. Optic disk: The size of the optic disk is the first to be studied normal, megalopapilla, micropapilla, alterations of the papilla in myopia, and hyperopia. Rims: Normal, distinct, and diffuse. Color: Normal pink, hyperemia, and paleness. Cupping: Normal or altered, glaucomatous cupping, pseudoglaucomatous cupping, edematous papillae, usually when there is conflict of intracranial space.
R. Sampaolesi et al., The Glaucomas, DOI 10.1007/978-3-642-35500-4_24, © Springer-Verlag Berlin Heidelberg 2014
341
24
342 15°
10°
5°
V=1
V = 0.3
Ophthalmoscopy
V = 0.2
6° = 1.6 mm
1 mm2
5°30' = 1.5 mm
400 μ
8° = 2.14 mm 20° = 5.36 mm
200 μ
Fig. 24.1 Amsler’s diagram
Study of the center of the retina: Normal macula, normal central macular reflex, its alteration or disappearance. Then the peripheral macular reflex is studied, which may be normal, altered, or similar. In the macular area, if the pigment epithelium is preserved and normal, it prevents seeing the choroidal vessels. If the choroidal vessels are visible, this is a first pathology showing that the pigment epithelium is altered. Figure 24.1, taken from Amsler, shows the area between the disk and the macula with its limits and dimensions in millimeters and degrees.
24.2
Ophthalmoscopes and Lenses for Studying the Fundus Oculi
For this study, the following elements are used: ophthalmoscope, aerial lenses, contact lenses, drawings, red-free light photography, retinographies, optic disk confocal tomography, and SL-OCT (Fig. 24.2a, b).
24.3
Alterations of the Optic Nerve Head
Figure 24.12 shows the importance of the retinofluorescein in order to diagnose a hypoperfusion of
