Page 928 - Atlas of Histology with Functional Correlations

FIGURE 22.12 | Section of Posterior Retina with

Yellow Pigment of Macula Lutea

With special stains, it is possible to see the yellow area of the macula lutea in the
posterior region of the retina. The macula lutea is a small yellow area that

surrounds the retinal depression (fovea) and is closely located to the optic disk in
the posterior region of the eyeball. This micrograph image shows the yellow
color of the macula lutea that is due to the accumulated yellow pigment

(xanthophyll) (7) in the ganglion cells from the fovea. The ganglion cell layer
(2) and the retinal axons (1) are displaced laterally off the fovea so that the light
can pass unimpeded to the sensitive cone cells in the center of the fovea. With
this stain are also visible the ganglion cell layer (2), the inner plexiform layer
(8), the inner nuclear layer (3), the outer plexiform layer (9), the outer

nuclear layer (4), and the photoreceptors cells—the rods and cones (10).
Barely visible is the pigment epithelium (5) layer that is adjacent to the dense-
staining choroid (6). Surrounding the retina is the connective tissue sclera (11).

FIGURE 22.12 ■ A section of the posterior retina with the yellow pigment of
the macula lutea. Stain: gold and yellow. ×100.

FUNCTIONAL CORRELATIONS 22.1 ■ Eye

SECRETIONS (TEARS)

Each eyeball is covered on its anterior surface with thin eyelids and fine

hairs, eyelashes, located on the margins of the eyelids. Eyelids and eyelashes

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