The Human Brain During the Third Trimester

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PART VII:

GW29

CORONAL

PART VII:

GW29

CORONAL

Figure 9. Lateral view of a GW30 brain with major structures in the cerebral hemispheres labeled. This is

the same as Figure 7 repeated here for convenience. (From the photographic series of J. C. Larroche (1967)

Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus

et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London:

Blackwell, page 248.)

This specimen is case number W-14-59 (Perinatal RPSL) in the

Yakovlev Collection. A female fetus was prematurely stillborn after

intrauterine asphyxia. Autopsy notes include a subdural hemorrhage,

and there is a hemorrhage in the striatal germinal matrix on the left

side of many sections. However, the remainder of the brain appears

normal and is classified as a Normative Control in the Yakovlev Collec-

tion (Haleem, 1990). It was cut in the coronal plane in 35-μm and 15-μm

thick sections. Since there is no available photograph of this brain before

it was embedded and cut, the photograph of the lateral view of a GW30

brain that Larroche published in 1967 (Figure 9) is used.

The approximate cutting plane of this brain is indicated in Figure 10

(facing page) with lines superimposed on the GW30 brain from the Lar-

roche (1967) series. This brain is cut perpendicular to the longitudinal

axis of the cerebral hemispheres between the frontal and occipital poles

and is remarkably even in the medial/lateral plane (both temporal poles

appear in Level 3, Section 621). As in all other specimens, the sections

chosen for illustration are spaced closer together to show small struc-

tures in the diencephalon, midbrain, pons, and medulla. Illustrated sec-

tions are spaced farther apart when they contain only large brain struc-

tures, such as the cerebral cortex, basal ganglia, and cerebellum. Pho-

tographs of 20 different Nissl-stained sections (Levels 1-20) are shown

at low magnification in Plates 151-170. Different areas of the cerebral

cortex are shown at very high magnification in Plates 171-174. The core

of the brain and the cerebellum are shown at high magnification in com-

panion Plates 175AB-189AB for Levels 3-18.