Chapter 3

### Clinical Summary

#### Disk

The disk is pale pink, approximately 1.5 mm in diameter, with sharp, flat margins. The physiologic cup is located within the disk and usually measures less than six-tenths the disk diameter. The cups should be approximately equal in both eyes.

#### Vessels

The central retinal artery and central retinal vein travel within the optic nerve, branching near the surface into the inferior and superior branches of arterioles and venules, respectively. Normally the walls of the vessels are not visible; the column of blood within the walls is visualized. The venules are seen as branching, dark red lines. The arterioles are seen as bright red branching lines, approximately two-thirds or three-fourths the diameter of the venules.

#### Macula

This is an area of the retina located temporal to the disk; it is void of visible vessels. The fovea is an area of depression approximately 1.5 mm in diameter (similar to the optic disk) in the center of the macula. The foveola is a tiny pit located in the center of the fovea. These areas correspond to central vision.

#### Background

The background fundus is red; there is some variation in the color, depending on the amount of individual pigmentation and the visibility of the choroidal vessels beneath the retina.

###### Figure 3.1.

Normal Fundus. The disk has sharp margins and is normal in color, with a small central cup. Arterioles and venules have normal color, sheen, and course. Background is in normal color. The macula is enclosed by arching temporal vessels. The fovea is located by a central pit. (Photo contributor: Beverly C. Forcier, MD.)

#### Pearls

1. Fundal examination should be an integral part of any eye examination.

2. The cup/disk ratio is slightly larger in the African American population.

3. The normal fundus should be void of any hemorrhages, exudates, or tortuous vasculature.

### Clinical Summary

Age-related macular degeneration increases in incidence with each decade over 50 and is evidenced by accumulation of either hard drusen (small, discrete, round, punctate nodules), or soft drusen (larger, pale yellow or gray, without discrete margins that may be confluent). Most patients with drusen have good vision, although there may be decreased visual acuity and distortion of vision. There may be associated pigmentary changes and atrophy of the retina. Vision may slowly deteriorate if atrophy occurs.

Patients with early or late degenerative changes of the macula are at risk of developing choroidal neovascularization (CNV), which is associated with distortion of vision, blind spots, and decreased visual acuity. Macular appearance may show dirty gray lesions, hemorrhage, retinal elevation, and exudation.

### Emergency Department Treatment and Disposition

Patients with drusen ...

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